Students and Teachers Forum

1. In a survey , 3/14 children like only math and 70 don't like math at all. Also 9/14 children like science but 20 like none of them.

i) Show that above data in a Venn-diagram.
ii) How many children like both types of subjects?

Let, M and S denote the people who like Math and science respectively. Let, n(U) = x  n(M)' = 70, no(M) = 3x/14 , n(S) =9x/14, n(M∪S)' = 20 Now,  n(U) = no(S) + n(M) + n(M∪S)' or, x = 9x/14 + 3x/14 + .....

2. In a community of 700 people the ratio of people who like to eata orange only, apple and neither orange not apple is 1: 5: 1. Using Venn-diagram,find the number of people who dont like both of them.

Let, O and A denote the people who like orange and apple respectively. By the question, n(U) = 700 no(O) : n(A) : n(O U A)' = 1 : 5 : 1 So, no(A) = x n(O) = 5x  n(O ∪ A)'  = x Now, n(U) = no(O) .....

3. There are 40 students in maths class and 50 students in English class. Find the number of students who are either in maths class or in English class.

i) When two classes meet at difference hours and 15 students are enrolled in both classes.

ii)  When two classes meet at the same hour.

Here, n(A) = 35,       n(B) = 57,       n(A ∩ B) = 12  (Let A be the set of students in math class.  B be the set of students in english class.)  (i) When 2 classes meet at different hours n(A .....

4. There are 35 students in Music class and 57 students in Dance class. Find the number of students who are either in Music class or in Dance class.

i) When two classes meet at difference hours and 12 students are enrolled in both the classes.

ii) Whent wo classes meet at the same hour.
 

Here,  Students in music class = n(A) = 35, Students in dance class = n(B) = 57,       In both class = n(A ∩ B) = 12  (i) When 2 classes meet at different hours n(A ∪ B) = n(A) + n(B) - n(A ∩ .....

5. In a survey of 99 people, Hindus and Muslim are in the ratio of 4:3. If 5050/99% follow other religion, by drawing a Venn-diagram, find the number of the Hindus.

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6. In a survey done in a college it is found that, 240 have laptop and 60% have palmtop. Those who have palmtop also have laptop. If 20% do not have both then, 
i. Find the number of men who have participated in the survey.
ii. Find the number of men who have laptop only.

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7. A survey was done one day about daily newspapers Kantipur and Annapurna Post. 100 people bought Kantipur, 30 did not buy Kantipur, 44 did not buy Annapurna Post among them 22 bought Kantipur then using Venn-diagram find
(i) How many took part in the survey?
(ii)  How many bought Annapurna Post only?
 (iii) How many bought both the newspapers?

Here,  n(K) = 100 n(K') = 30 So, n(U) = 100 + 30 = 130 n(A') = 44 n(A) = 130 - 44 = 86. Use this diagram & find the .....

8. In a survey of mobile and telephone, it was found that, 200 people had telephone, 25 had both 135 didnot not have telephone and 300 did not have mobile.

i. How many people participated in the survey?
ii. How many had mobile only?

Here, n(T)  = 200 n(T∩M) = 25 n(T') = 135 n(M') = 300. We know,  (i) n(U) = n(T) + n(T')  = 200 + 135 = ...............Find it. (ii) n(M) = n(U) - n(M') = ......................find it. Again, no(M) = .....

9. In a survey of people, 40 people drink milk, 30 do not drink milk and 50 drink curd. If 25 drink curd not milk then how many do not drink both ? 

Here,  n(M) = 40 n(M') = 30 n(C) = 50 no(C) = 25. Here,  No.of people drink both = n(M∩C) = n(C) - no(C) = 50 - .....

10. In a group of 200 people, 60 like folk song, 20% like folk song but not pop song. If the ratio of people who like pop song only to who dislike both is 4 : 3, find the percentage of people who like only one.

Let,  n(U) = 200 n(F) = 60 no(F) = 20% of 200 = 40  no(P) = 4x n(FUP)' = 3x We know,  n(F∩P) = n(F) - no(F) = 20. Now,  n(FUP) = no(P) + no(F) + n(F∩P) or, 200 - 3x = 4x + 40 + 20 Find x. Then, Find no(F) .....

11. In a survey, 70 liked love marriage but not the arranged marriage when 16 liked arrange marriage but not the love marriage. If the number who like love marriage is three times the number who like arrange marriage, find the number of people who like both types of the marriages.

Here, no(A) = 70 no(L) = 16 Let x be the no.of people who like both. According to question, 3n(A) = n(L) or, 3( 70 + x ) = 16 + x Here, we get x -ve. So question is .....

12. If n(A) = 48. n(B) =51, n(C) = 40, n(A∩B) = 11, n(B∩C) = 10, n(C∩A) = 9. n(A∩B∩C) = 4 and n(U) = 120, find the values of n(A∪B ∪ C) and n( A ∪ B∪ C)'. Present the above information in a Venn-diagram.

Here, n(U) = 120 n(A) = 48 n(B) = 51 n(C) = 40 n(A∩B) = 11 n(B∩C) = 10 n(C∩A) = 9 n(A∩B∩C) = 4 n(AUBUC) = ? n(AUBUC)' = ? We know,  n(AUBUC) = n(A) + n(B) + n(C) -n(A∩B) - n(B∩C) - n(C∩A) + .....

13.  If n(A) =65, n(B) = 50, n(C) = 35, n(A ∩ B) = 25, n(B ∩C) = 20, n(C∩ A) = 15 , n(A ∩ B ∩ C) = 5 and n(U) = 100, find the value of n (A ∪ B ∪ C)'

Here, n(U) = 100 n(A) = 65 n(B) = 50 n(C) = 35 n(A∩B) = 25 n(B∩C) = 20 n(C∩A) = 15 n(A∩B∩C) = 5 n(AUBUC)' = ? We know,  n(AUBUC) = n(A) + n(B) + n(C) -n(A∩B) - n(B∩C) - n(C∩A) + .....

14. The number of  degree in an angle exceeds 14 times the number of radius in it by 51. Find the sexagesimal measure of he angle.

Let angle be x. Then x = 14xc + 51 or, x  - 14x ⨯ π/180 = 51 or, x - 11x / 45 = 51 or, 34x = 51 ⨯ 45  or, x = 51 ⨯ 45 / 34 or, x = .....

15. What will happen if oil is used in hot water bags instead of water?

We use water because, It’s not toxic and non-damaging if it spills It can’t be heated to temperatures which would melt hot water bags Though it can be heated enough to scald, hot oil would be far hotter and cause more severe .....

16. The total price of 4 copies and 5 books is rs 880.If the price of one book is rs 128 what is the cost price of one copy.

Here,  Cost of 1 book = Rs.128 So, cost of 5 book = 5 ⨯ Rs.128 = Rs.640 Now,       Cost of 4 copies + cost of 5 book = Rs.880 or, Cost of 4 copies + Rs.640 = Rs.880 or, Cost of 4 copies  = Rs.880 .....

17. Why did Jung Bahadur murder Gagan Singh?

After the murder of the then Prime Minister Mathawar Singh Thapa, Chautariya Fatey Jung became the Prime Minister of Nepal. However, more power lay in the hands of Gagan Singh as he was Queen Rajya Laxmi’s favourite and he also controlled .....

18. Describe the activity to seprate the colour pigments with the help of suitable diagram.

Chromatography is the science of separation and is used in the chemical industry in many forms from purifying chemicals in a reaction, studying the contents of water, to testing for the presence of illegal compounds in athletes. Compounds in a .....

19. If each side of an equilateral triangle is increased by 2cm then its area increases by 3 rootover 3 cm^2 . Calculate the length of each of its side and its area

Let a be the side of an equilateral triangle. Then, Area = a2√3/4 According to question, (a+2)2√3/4 - a2√3/4 = 3√3 or, (a + 2)2 - a2 = 12 or, 4a + 4 = 12 or, a = 2cm Now,  Area  .....

20. भुतल भन्य के हो ?

भूतल : यो संस्कृत शब्द हो । नेपाली बृहत् शब्दकोशका अनुसार :  पृथ्वीको बाहिरी खँदिलो .....

21. What measures should be taken to prevent from the negative effects of climate change?

The factors affecting climate change are as follows: - Presence of greenhouse gases in a large amount in the atmosphere. - Changes in ocean currents, which shift air currents - Urbanization and the destruction of natural habitats. - Factory and .....

22. When was Save the Children established? Write its one major function.

It was established with the view to improve the lives of children through better education, health care, and economic aid. It helps to protect and promote children's rights. It provides relief and helps support children in developing .....

23. बलात्कार को परिभाषा र त्यस्को कारन र परिभाषा ?

बलात्कार : कसैको मन्जुरी बिना करकाप, डर, धम्कि वा बल प्रयोग गरि जबरजस्ति गरिने यौनसम्पर्कलाई .....

24. Write a program to declare a user defined function arm(n) to input a number and check whether it is an armstrong number.

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25. Wap to print string and find sum of ascii value

CLS INPUT "enter any string"; n$ l = LEN(n$) Sum=0; PRINT "Character", "Ascii value" FOR i = 1 TO l m$ = MID$(n$, i, 1) PRINT m$; TAB(20); ASC(m$) NEXT i Sum=Sum+m$; PRINT .....

26. Fill in the blanks.
i) Zinc + ............. ⟶ Zinc Chloride  + Hydrogen
ii) Coper Oxide  + Hydrogen ⟶ ................  + Water
iii) KClO2 ⟶   ................ + O2
iv) CH4 + .................. ⟶ CO2 + H2O

1. Zn + HCl → H2 + ZnCl2 2. CuO + H2 → Cu + H2O 3. KClO2 → KCl + O2 4. CH4 + O2 .....

27. Simplify:
70÷14×6-40+2×20

Using the BODMAS rule, = 70  ∕ 14 ∗ 6 - 40 + 2 ∗ 20 = 5 ∗ 6 - 40 + 2 ∗ 20 [ Dividing 70 by 14 to get 5 ] = 30 - 40 + 40 [ Multiplying 5 and 6, 2 and 20 ] = 30 + 40 - 40  = 70 - 40 [ Adding .....

28. ईन्टरनेट का फाइद हरु लेख्नुस

sDKo'6/ / OG6/g]6 .....

29. At 40degree C 45 gram potassium chloride dissolves in 30 g of water to form saturated solution . Find the solubility of potassium chloride.

Here,solute = 30 gm Solvent = 45 - 30 =15 Now, solubility = solute x 100                              solvent               .....

30. Prove that: (secA - tanA)/(secA + tanA) = cos2A/(1 + sinA)2

Here take LHS and Multiply numerator and denomerator by secA+tanA Now you will get         (sec2A-Tan2A)/(secA+tanA)2 Then put (sec2A-tan2A)=1 = 1/(secA+tanA)2 Now, change sec and tan in to cos and sin and .....

31. Why do you need child rights ?

- Children’s rights help to the all-round development of the child. - Child rights help the children to grow them as a full-fledged member of a society or a .....

32. In the figure given aside, the diagonals ac and bd meet at o such that oa=oc and ob=od,prove that abcd is a parallelogram

Here, Given, OA = OC & OB = OD. Now,  Take triangle AOB & DOC.  Show them congurrent by SAS axiom. Then, angle ABO = angle CDO     Thus, AB//CD. Similarly AD//BC. Now you can write the .....

33. In the figure given aside, ab=dc and bc=ad,prove that abcd is a parallelogram

Given,  AB = CD  & BC = AD. To prove: ABCD is //gm. Take two triangles  ABC & ADC. Show thwem congurrent by SSS axiom. Then, Show angles BAC = ACD. Thus, AB // CD as alternate angles are equal. Similarly, .....

34. If p,Q,R and S are the vertices of a parallelogram PQRS taken in order and the co ordinates of P and Q are (7,16) and (10,2) and the point of intersection of its diagonals is (2,6). Find the coordinates of R and S.

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35. How does energy transformation take place in a transistor operated with a battery?

In this case, when transistor is operated with bacteries, chemical energy inside the battery is converted into electrical energy and finally operate .....

36. Find the value of x and y.

Here, In triangle OAT y = 90o - 40o = 50o     [ Since, ∡OAT = 90o.] Now,  ∡OBC = x               [ Since, OC = OB.] Thus,  x + x = y or, 2x = 50 Find .....

37. Compare and contrast between mendeleev's and moseley's periodic table?

Mendeleev vs Moseley Periodic Table

Mendeleev Periodic Table was proposed by Dimitri Mendeleev in 1869. The well-organized periodic table containing chemical elements arranged based on their atomic numbers was .....

38. Solve:
a/3-a/4=1

Here, We have given a/3 - a/4 = 1 Taking LCF of 3 & 4, we get 12 So,  a/3 - a/4 = 1 or, ( 4a - 3a) / 12 = 1 or, a/ 12=  1 or, a = 1 ⨯ 12 Thus, a = 12 is .....

39. A Nepali worker earns Qatari Riyal( QAR ) 1800 per month in Qatar. If the exchange rate is QAR 1 = Rs 29.25, how much is the yearly salary of the worker in Nepali rupees? [ Ans. 631800 ]

Monthly income of the nepali worker = 1,800 riyal Exchange rate is : 1 Riyal = Rs. 29.25 Therefore his monthly income in nepali rupee = Rs. (29.25 x 1800) = Rs. 52650 Yearly salary = Rs. 52650 ∗ 12 = Rs. .....

40. The buying rate and selling rate of $1 in a money exchange centre are Rs. 105.50 and Rs. 106.40 respectively. If $ 5000 is bought and sold by the money exchange centre, what is the profit in NRs?

Exchange rate while buying, $1 = Rs 105.50 Exchange rate while selling, $1 = Rs 106.40 Total amount = $5000 While buying amount in NRs = Rs. 5000 ∗ 105.50 = Rs. 527500 While selling the amount in NRs = Rs. 5000 ∗ 106.40 = .....

41. Countries of savanna have developed their tourism and have made a huge benefit in their economy. What can Nepal learn from them? Write in four points.

So, Nepal should learn the following lessons from the countries of Savana region: - Nepal is full of natural resources which has the prospects of tourism industry and can earn foreign   currency as Keny had done. - Around 43% of the total .....

42. Solve (0°≤A≤360°)
1+√3tanA-secA=0

Here, 1+√3tanA-secA=0 or, √3tanA = secA - 1 Squaring both sides, we get 3tan2A = sec2A - 2secA + 1 or, 3(sec2A - 1) = sec2A - 2secA + 1 or, 2sec2A + 2secA - 4 = 0 or, sec2A + secA - 2 = 0 or, sec2A + 2secA .....

43. Match the following.

a) frustrating                   i) a pipe for carrying rainwater or liquid refuse
b) jam-packed                 ii) go against a rule
c) drain pipe                    iii) the vehicles on a road
d) violate                         iv) very full or crowded
e) traffic                           v) to feel upset or annoyed

a = v b = iv c = i d = ii e = .....

44. Solve (0° to 360°)
√3 sina+cosa=√2

Here, √3 sina+cosa=√2 or, √3 sina=√2 - cosa Squaring both sides, we get 3 sin2a  = 2 - 2√2cosa + cos2a or, 3( 1 - cos2a) - 2 + 2√2cosa - cos2a = 0 or, 4cos2a - 2√2cosa - 1 =0 Now .....

45. What is meant by parliamentary supremacy? What provisions have made in the constitution of Nepal regarding parliamentary supremacy?

Parliamentary supremacy is the key to institutionalize democracy in Nepal. It plays important roles in realizing the idea of constitutional supremacy, ensuring a limited government, making effective and efficient laws, and empowering the people, .....

46. Write four major physical features of the hilly region.

It occupies 68% of the total land of the country. It is situated to the north of Terai with an altitude ranging from 600m to 3300m above the sea level. This region extends from Mechi in the East to Mahakali in the West. The width of this region .....

47. In absence of energy a person is just like an inanimate matter. Justify the statement.

Our body is made up of cells, tissues, and organs. Each cell functions with the help of energy produced within it. In the absence of energy, no cells can function and hence organs or our body cannot function at all. In other words, a body becomes .....

48. Which is the coldest region in the world?

Verkhoyansk in Russia is considered one of the coldest place of the world. This place is located at 1,500 miles south of the North Pole and 404 miles away from Yakutsk.  The average temperature is – 50.4 degrees F. The lowest .....

49. Find L.C.M of:6ax²(a+b),9a²x(a²-b²)

Here, First expression = 6ax2( a + b)                             = 2.3.a.x.x( a + b) Second expression = 9a2x( a2 - b2)             .....

50. What is an osculum?

The osculum is an excretory structure in the living sponge, a large opening to the outside through which the current of water exits after passing through the .....