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1. The average temperature for Monday, Tuesday, Wednesday and Thursday was 48 degrees and for Tuesday, Wednesday, Thursday and Friday was 46 degrees. If the temperature on Monday was 42 degrees. Find the temperature on Friday ?
Options
A. 34
B. 36
C. 38
D. 40

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2. The average weight of 45 passengers in a bus is 52 kg. 5 of them whose average weight is 48 kg leave the bus and other 5 passengers whose average weight is 54 kg join the bus at the same stop. What is the new average weight of the bus?
Options
A. 54.21 kgs
B. 51.07 kgs
C. 52.66 kgs
D. 53.45 kgs

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3. 19 friends went to a restaurant for a combined weekend dinner party. 13 of them spent Rs. 79 each on their dinner and the rest spent Rs. 4 more than the average expenditure of all the 19. What was the total money spent by them?
Options
A. Rs. 1398.96
B. Rs. 1457.09
C. Rs. 1662.35
D. Rs. 1536.07

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4. If the average height of boys in a hall is 180 cm and that of girls is 150 cm. If the average height of the gathering is 165 cm, then find the number of girls present in the hall if the number of boys present in the hall are 78 ?
Options
A. 56
B. 64
C. 87
D. 78

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5. If the mean of a, b, c is M and ab + bc + ca = 0, then the mean of a2+b2+c23 is :
Options
A. M
B. 3 M^2
C. 2 (M/3)
D. M^2

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Correct Answer: 3 M^2

Explanation:

We have : ( a + b + c) / 3 = M or (a + b + c) = 3M.

Now. ${(a + b + c)}^{2} = {(3 M)}^{2} = 9 M^{2}$ .

$< = > a^{2} + b^{2} + c^{2} + 2 (a b + b c + c a) = 9 M^{2}$

$a^{2} + b^{2} + c^{2} = 9 M^{2}, (a b + b c + c a = 0)$

Required mean = $(\frac{a^{2} + b^{2} + c^{2}}{3}) = \frac{9 M^{2}}{3} = 3 M^{2}$ .

6. 12 boys decided to constribute Rs. 750 each to an Orphange. Suddenly few of them boys dropped out and consequently the rest had to pay Rs. 150 more. Then the number of boys who dropped out?
Options
A. 4
B. 6
C. 2
D. 3

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7. The average score of boys in an examination in a school is 81 and that of the girls is 83 and the average score of the school is 81.8. Then what will be ratio between the number of girls to the number of boys, in the examination?
Options
A. 3:2
B. 2:3
C. 4:3
D. 3:4

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8. A student's average marks in five subjects is 82. If the average marks of first two subject is 86.5 and the average marks of last two subjects is 84. Find the marks of third subject?
Options
A. 69
B. 67
C. 71
D. 73

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9. A batsman in his 17th innings makes a score of 85 and their by increasing his average by 3. What is his average after the 17th innings ?
Options
A. 34
B. 36
C. 35
D. 37

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