# ZS Associates Questions on Averages with Solutions

Question 1 Time: 00:00:00
```The mean weight of a group of seven boys is 56 kg. The individual
weights (in kg) of six of them are 52, 57, 55, 60, 59 and 55.
Find the weight of the seventh boy?``` 57 kg

57 kg

54 kg

54 kg

53 kg

53 kg

55 kg

55 kg

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The answer is \" four\"As we know that the 29th February came after every four years. So according to that 26 total birthday will be celebrated in 101 years. Also after every years date are moved by 1 so in every birthday date will be moved by 5 days . This means wednesday will came on every 7th birthday of the john . So by simple calculation total 4 birthdays will be on the wednesday. That day will be on 1st , 8th , 15th and 22th birthday.

must have

As they have given new price is not less than half the original price therefore 164.90/2= 82.45 And new price is more than 82.45 Considering the options it would be 97.

m+n=8....(1) m-n=6.....(2) solving equation 1 and 2 we get m=7 and n=1 according to given condition mn 7*1=7 7%6=1 so the rem. is 1

option b is the correct answer.

c+1 means c is base address i.e. address of 1st one Dimensional array and on incrementing it by 1 means it points to 2nd one 2 Dimensional array. So, c+1=65474 + ( 4 * 2)= 65482 But, when we are writing &c, that means address of this whole array i.e. address of next new array. So, &c+1=65474 + (12 * 2)=65498

for cout the operator overloaded is <<

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Question 2 Time: 00:00:00
```Average weight of 25 boys in a class is 48 kgs. The average
weight of the class of 40 students is 45 kgs. What is the
average weight of the 15 girls in the class?
39 kgs``` 42 kgs

42 kgs

42.5 kgs

42.5 kgs

40 kgs

40 kgs

44 kgs

44 kgs

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x++ is not executed inside sizeof function

n(n-3)/2=77 n^2-3n=154 n^2-3n-154=0 n=-11,14

if side of a polygon=n then diagonal=n(n-3)/2

x++ is not executed inside sizeof function

Set P = {4, 8, 12, ….496} ? 124 elements {all elements from 1 * 4 to 124 * 4} Set Q = {7, 21, 35, 49,……497} ? {7 * 1, 7 * 3, 7 * 5, ….. 7 * 71} ? 36 elements. Set R = {6, 12, 18, 24, …..498} ? {6 * 1, 6 * 2, 6 * 3, ….. 6 * 83} ? 83 elements. Sets P and R have only even numbers; set Q has only odd numbers. So, P ? Q = Null set Q ? R = Null set P ? Q ? R = Null set So, If we find P ? R , we can plug into the formula and get P ? Q ? R P ? R = Set of all multiples of 12 less than 500 = {12, 24, 36,…..492} = {12 * 1, 12 * 2 , 12 * 3, …12 * 41} ? This has 41 elements P ? Q ? R = P + Q + R – (P ? Q) – ( Q ? R) – (R ? P) + (P ? Q ? R) P ? Q ? R = 124 + 36 + 83 – 0 – 0 – 41 + 0 = 202 The question is \"How many elements are present in P ? Q ? R?\" Hence, the answer is \"202\".

decided

There is no return type given for the MyDisplay we need to consider it as null or we can take it as a string hence the integer cannot be returned.

Only if n==1, then sum is equal to one. So , if n is 1 then it should directly return 1.

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Question 3 Time: 00:00:00
```A pupil's marks were wrongly entered as 83 instead of 63. Due to
that the average marks for the class got increased by half.
The number of pupils in the class is?``` 47

47

44

44

39

39

40

40

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check the recursive function it fails for the n=1 hence the terminating condition will be the 1

reached

The only thing to observe here is that every term beyond and including 4! is a multiple of 24. So, their contribution to the remainder will be 0. Simply adding up the first 3 terms, we get 1+2+6=9.

18*6 and 7 and 8 and 9 and 10 and 11. Answer is 6

0.1 by default is of type double which has different representation than float resulting in inequality even after conversion.

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Question 4 Time: 00:00:00
```Average of age 3 men L, M and N is 48 years. Another man O joins
the group and the average becomes 44 years. If another man P whose
age is 3 years more than that of O replaces L.
Then the average age of M, N, O and P becomes 43 years then
the age of L is?``` 39

39

36

36

35

35

40

40

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0.0056=56/10000=7/1250

the speed of first car must be 50 kmph.

x+X+20+x-20=120 3x=120 x=40 x is A\'s share so B\'s share is 20

x+X+20+x-20=120 3x=120 x=40 x is A\'s share so B\'s share is 20

It is given as an unsigned integer hence it can store only -32 to 31 but not 32

use the recursion tree

given 58 not 50

ratio of eff. of a & c=5:3 so, eff. of a is more than c and a takes 6 day less than c so,day takes by a & c=9 day and 15 day respectively ratio of no. of day b & c=2:3 means day required =10 & 15 day respectively therefore, no of day taken by a ,b,c=9,10,15 respectively so, total work=90( LCM of no of days) a completed 10 units of work in one day same b is 9 unit and c is 6 unit in a day total work done by all in 1 day=(10+9+6)=25 in two days +25*2=50(in two days remaining work is 40 unit completed by a ) so a takes 4 days to complete the remaining work.

ratio of eff. of a & c=5:3 so, eff. of a is more than c and a takes 6 day less than c so,day takes by a & c=9 day and 15 day respectively ratio of no. of day b & c=2:3 means day required =10 & 15 day respectively therefore, no of day taken by a ,b,c=9,10,15 respectively so, total work=90( LCM of no of days) a completed 10 units of work in one day same b is 9 unit and c is 6 unit in a day total work done by all in 1 day=(10+9+6)=25 in two days +25*2=50(in two days remaining work is 40 unit completed by a ) so a takes 4 days to complete the remaining work.

Answer: b Explanation: signed char will be a negative number. Output: \$ cc pgm2.c \$ a.out -128

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Question 5 Time: 00:00:00
```Amith starts to work on the first day. On the second day two more
friends join him. On the third day 3 more friends join him and so
on they complete work in 30 days. The find the number of days 16 girls
can finish the work completely given that a girl can work twice as
fast as Amith and his friends.(Assume all friends of Amith as Boys)``` 126

126

155

155

140

140

136

136

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answer is wrong ,correct is 155 Let Amith or his friend alone can complete the work in \'x\' days, then 1 day work of Amith=1 day work of his friend=1/x Their 30 day\'s work=1/x + 3/x + 6/x + 10/x .... =1 => 1/x (1 + 3 + 6 + 10 +....upto 30 terms)=1 Sequence 1,3,6,10,15,... is called triangle number series with sum=n(n+1)(n+2)/6 => (1/x) (30*31*32/2) =1 => 1/x=1/4960 As girl is of twice capacity of a boy, so 1 girl\'s 1 day work = 2*(1/x)=2*1/4960=1/2480 So 16 girl\'s 1 day work=16*(1/2480)=1/155 Hence required days=155

told

string

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Question 6 Time: 00:00:00
```If P=(102 power x) - (98 power x) and x is a natural number greater
than zero. how many values exist at units place of P?``` 4

4

5

5

3

3

8

8

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Question 7 Time: 00:00:00
```A packet of toffees is distributed in a class. A child who
receives one-eighth of the total number of
toffees get five times the average number of toffees received
by the remaining children in the class.
What is the strength of the class?``` 40

40

35

35

36

36

none of the above

none of the above

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Question 8 Time: 00:00:00
```Four of the six numbers is 1867456,1993764,2019657,2025189,
2109472,2121346 have a mean of 2068916.What is the mean of
other two numbers``` 2006710.5

2006710.5

2067330.5

2067330.5

1930610

1930610

2022423

2022423

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Question 9 Time: 00:00:00
```The average temperature of June, July, and August was 31 degrees.
The average temperature for July, August, and September was
30 degrees. If the temperature of June was 30 degrees,
find the temperature of September (in degrees).``` 25

25

26

26

27

27

28

28

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Question 10 Time: 00:00:00
```You need a 18% acid solution for a certain test, but your supplier
only ships a 13% solution and a 43% solution. You need 120 lts of
the 18% acid solution. the 13% solution costs Rs 82 per ltr for the
first 67 ltrs, and Rs 66 per ltr for any amount in excess of 67 liters.
What is the cost of the 13% solution you should buy?``` 8002

8002

7012

7012

7672

7672

7342

7342

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