Question
A’s present age is double B’s present age. After 6
years, A’s age will be four times the present age of C. The ratio of B’s age 3 years ago to C’s age 1 year hence is 2:3. If D’s present age is three times A’s present age, find D’s present age.Solution
ATQ, Let, the present age of B = x years So, the present age of A = 2x years Let, the present age of C = y years After 6 years, A’s age will be four times the present age of C 2x + 6 = 4y y = (2x + 6)/4 y = (x + 3)/2 Given ratio: (B’s age 3 years ago) : (C’s age 1 year hence) = 2 : 3 (x - 3)/(y + 1) = 2/3 (x - 3)/((x + 3)/2 + 1) = 2/3 (x - 3)/((x + 3 + 2)/2) = 2/3 (x - 3)/((x + 5)/2) = 2/3 2(x - 3)/(x + 5) = 2/3 6(x - 3) = 2(x + 5) 6x - 18 = 2x + 10 4x = 28 x = 7 Present age of A = 2x = 14 years Present age of D = 3*(Age of A) = 3*14 = 42 years
- Determine the value of ‘x’ if (7 × 256 – 525 ÷ 21) ÷ 28 = √2500 – x.
What will come in the place of question mark (?) in the given expression?
737 + 149 - ?²- 367 = 14 X 25- What will come in place of (?), in the given expression.
3² × 5 + 2³ × 4 = ? Simplify the following expressions and choose the correct option.
(3/7) of {350 − [42 ÷ (3/2)]} = ?
What should come in place of (?) question mark in the given expression.
{ 5 × [ (36 ÷ 3) + (64 ÷ 8) ] } − (4³) = ?
(320 + 342 + 530 + 915) ÷ (20 + 22 – x + 18) = 43, then the value of x is:
√676 + (0.75 × 80) + (72 ÷ 3) = ? - 82
9/5 × 18/25 ÷ 42/21 = ? - 82/75
√121 + √961− √289 =?2