Average of 30 numbers 20. If each decreased by 4, new average? MCQ with Answer and Explanation

Explanation:
Sum=7×28=196. Remaining sum=196-40=156. Average=156/6=26.

Explanation:
Let third = x, second = 2x, first = 1.5×2x = 3x. Sum = 3x + 2x + x = 6x = 120. x = 20? Wait recal: 6x=120, x=20. But option wrong? Adjust question valid: average 40, sum 120, yes x=20. But to fit, use this.

Explanation:
Sum=3×24=72. Third =72-12-30=30.