Mathmetics
ISBT Mathmetics for all banking PO,Clerk,IBPS PO,Railway,SSC,IAS,OAS Exams
Q1. 

1)  33 years  2)  40 years 
3)  43 years  4)  48 years 
5)  None of these 
Answer : 43 years
Explanation :
Explanation :
Present age of C = 85 – 7 = 78 years
Present age of B = 78 – 12 = 66 years
Present age of A = 3
11 66 = 18 years
Present age of A’s father = 18 + 25 = 43 years
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Q2. 

1)  30 yrs  2)  24 yrs 
3)  18 yrs  4)  36 yrs 
5)  None of these 
Answer : 30 yrs
Explanation : The present age of C = 72  42 = 30 years
Explanation : The present age of C = 72  42 = 30 years
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Q3. 

1)  4 years  2)  6 years 
3)  8 years  4)  12 years 
5)  None of these 
Answer : 6 years
Explanation :
Explanation :
Mother's age when Prasant's brother was born = 46 years.
Father's age when Prasant's brother was born = (48 + 4) years = 52 years.
Required difference = (52  46) years = 6 years.
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Q4. 

1)  16 years  2)  18 years 
3)  20 years  4)  24 years 
5)  None of these 
Answer : 20 years
Explanation :
Explanation :
Let, the present ages of Alok and Prakash be x and (60 x) years respectively.
Then, (60  x)  6 = 5(x  6)
54  x = 5x  30
or 6x = 84
or x = 14.
So, Prakash's age after 6 years = (x+ 6) = 20 years.
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Q5. 

1)  14 years  2)  19 years 
3)  24 years  4)  28 years 
5)  None of these 
Answer : 19 years
Explanation :
Explanation :
Let, B's present age be x years. Then, (48  x) = x
Or 2x = 48.
Or x = 24.
B's age 5 years back (24  5) = 19 years.
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Q6. 

1)  29 yrs  2)  35 yrs 
3)  31 yrs  4)  33 yrs 
5)  None of these 
Answer : 31 yrs
Explanation :
Explanation :
Let, the present ages of A and B be 2x years and 3x years respectively.
So, (2x4)/(3x4) = 5/8
or 16x  32 = 15x 20
or x = 12
Therefore, the Ages of A after 7 years = 2x + 7 = 2 x 12 + 7 = 31 years
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Q7. 

1)  30 yrs  2)  24 yrs 
3)  18 yrs  4)  36 yrs 
5)  None of these 
Answer : 30 yrs
Explanation : The present age of Vijay = 72  42 = 30 years
Explanation : The present age of Vijay = 72  42 = 30 years
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Q8. 

1)  20 years  2)  22 years 
3)  18 years  4)  24 years 
5)  None of these 
Answer : 20 years
Explanation :
Explanation :
Let the shalini's and Sonal's present ages be 11x and 13 x years respectively.
After 3 years
13x + 3 = 29 or 13x = 29  3 = 26
X = 36/18 = 2
Shalini's age 2 years ago.
11x 2 = 11 x 2  2 = 20 years.
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Q9. 

1)  1 year  2)  2 year 
3)  25 year  4)  Can't be determined 
5)  None of these 
Answer : Can't be determined
Explanation :
Explanation :
Given that,
The difference of age R and Q = The difference of age Q and T.
Sum of age of R and T is 50 i.e. (R + T) = 50.
Then, R  Q = Q  T
or (R + T) = 2Q
Now given that, (R + T) = 50
So, 50 = 2Q and therefore Q = 25.
Question is (R  Q) = ?
Here we know the value(age) of Q (25), but we don't know the age of R.
Therefore, (RQ) cannot be determined.
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Q10. 

1)  12 years  2)  14 years 
3)  18 years  4)  20 years 
5)  None of these 
Answer : 20 years
Explanation :
Explanation :
Let, the present ages of son and father be x and (60 x) years respectively.
Then, (60  x)  6 = 5(x  6)
or 54  x = 5x  30
or 6x = 84
or x = 14.
Son's age after 6 years = (x + 6) = 20 years.
View Answer