If x varies indirectly to y2 and if x = 78, y = 11, then find the value of x when y = 2.2.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 1950.
x ∝ 1 / y²
So, x × y² = constant
Given: x = 78, y = 11
→ 78 × 11² = constant = 78 × 121 = 9438
Now, y = 2.2
x = 9438 / (2.2)² = 9438 / 4.84 ≈ 1950