9
Q:
A) 40 | B) 50 |
C) 60 | D) 70 |
Answer: B) 50
Explanation:
Explanation:
Sony and her brother's age sum is 31
Let Sony's mother's age be 'x'.
Now the conditions given for both of their ages related to their mom is
1/5(x-15) + 3/5(x-10) = 31
x-15 + 3x-30 = 155
4x-45 = 155
4x = 200
x = 50
So, Mother's age = 50.
Cross verification : 15 years ago age = 35 => Sony age = 7
10 years ago age = 40 => bro age = 24
Sum = 24 + 7 = 31.