23 years
24 years
25 years
None of these
Ans.- A
Let the average age of the whole team by x years.
11x - (26 + 29) = 9(x -1)
11x - 9x = 46
2x = 46
x = 23
So, average age of the team is 23 years
Let the average age of the whole team by x years.
11x - (26 + 29) = 9(x -1)
11x - 9x = 46
2x = 46
x = 23
So, average age of the team is 23 years
Q2)-Average age of boys in a class is 16 years and average age of girls is 15 years, what is the average age of all ?
15.5
15
16
Cant be determined
Ans.- D
As number of girls and boys is not given so result cant be determined
As number of girls and boys is not given so result cant be determined
Q3)-A batsman makes a score of 87 runs in the 17th match and thus increases his average by 3. Find his average after 17th match
37
36
39
35
Ans.- C
Let the average after 17th match is x
then the average before 17th match is x-3
so 16(x-3) + 87 = 17x
x = 87 - 48 = 39
Let the average after 17th match is x
then the average before 17th match is x-3
so 16(x-3) + 87 = 17x
x = 87 - 48 = 39
Q4)-The average of five consecutive odd numbers is 61. What is the difference between the highest and lowest numbers :
4
8
12
16
Ans.- B
Let the numbers be x, x + 2, x + 4, x + 6 and x + 8.
Then [x + (x + 2) + (x + 4) + (x + 6) + (x + 8) ] / 5 = 61.
or 5x + 20 = 305 or x = 57.
So, required difference = (57 + 8) - 57 = 8
Let the numbers be x, x + 2, x + 4, x + 6 and x + 8.
Then [x + (x + 2) + (x + 4) + (x + 6) + (x + 8) ] / 5 = 61.
or 5x + 20 = 305 or x = 57.
So, required difference = (57 + 8) - 57 = 8
Q5)-Average of five numbers is 27. If one number is excluded the average becomes 25. The excluded number is
35
45
55
65
Ans.- A
Number is (5*27) - (4*25) = 135-100 = 35
Number is (5*27) - (4*25) = 135-100 = 35
Q6)-In the first 10 overs of a cricket game, the run rate was only 3.2. What should be the run rate in the remaining 40 overs to reach the target of 282 runs?
5.5
5
6.25
7.4
Ans.- C
Runs scored in the first 10 overs = 10 × 3.2 = 32
Total runs = 282
Remaining runs to be scored = 282 - 32 = 250
Remaining overs = 40
Run rate needed =250/40=6.25
Runs scored in the first 10 overs = 10 × 3.2 = 32
Total runs = 282
Remaining runs to be scored = 282 - 32 = 250
Remaining overs = 40
Run rate needed =250/40=6.25
Q7)-The average weight of 8 persons increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person ?
70 kg
75 kg
80 kg
85 kg
Ans.- D
Total weight increased = (8 x 2.5) kg = 20 kg.
Weight of new person = (65 + 20) kg = 85 kg.
Total weight increased = (8 x 2.5) kg = 20 kg.
Weight of new person = (65 + 20) kg = 85 kg.
Q8)-The average age of a class of 39 students is 15 years. If the age of the teacher be included, then the average increases by 3 months. Find the age of the teacher.
20 years
25 years
28 years
30 years
Ans.- B
Total age of 39 students = (39x15) years = 585 years
Average age of 40 persons = 15 years 3 months = 61/4 years
Total age of of 40 persons = (61/4) x 40 years = 610 years
So, age of the teacher = 610 - 585 years = 25 years
Total age of 39 students = (39x15) years = 585 years
Average age of 40 persons = 15 years 3 months = 61/4 years
Total age of of 40 persons = (61/4) x 40 years = 610 years
So, age of the teacher = 610 - 585 years = 25 years
Q9)-The average weight of A, B & C is 45 Kg. If the average weight of A and B be 40 Kg and that of B & C be 43 Kg than the weight of B is :
17 kg
20 kg
22 kg
31 kg
Ans.- D
Let A, B & C represent their respective weights,
then we have A+B+C = 45 x 3 = 135 ......(i)
A+B = 40 x 2 = 80 ..........(ii)
B+C = 43 x 2 = 86 ...............(iii)
Adding equation (ii) & (iii) , we get A+2B+C = 166 ...........(iv)
Subtracting equation (i) from equation (iv),
we get B = 31, So, B's weight = 31 Kg.
Let A, B & C represent their respective weights,
then we have A+B+C = 45 x 3 = 135 ......(i)
A+B = 40 x 2 = 80 ..........(ii)
B+C = 43 x 2 = 86 ...............(iii)
Adding equation (ii) & (iii) , we get A+2B+C = 166 ...........(iv)
Subtracting equation (i) from equation (iv),
we get B = 31, So, B's weight = 31 Kg.
Q10)-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 :
35
38
40
45
Ans.- C
Let there be x pupils in the class.
Total increase in marks = (x * 1/2) = x/2.
x/2 = (83 - 63) => x/2 = 20 => x = 40.
Let there be x pupils in the class.
Total increase in marks = (x * 1/2) = x/2.
x/2 = (83 - 63) => x/2 = 20 => x = 40.
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