The average of a few numbers is 48. If 75% of the numbers are increased by 4 each and the rest are decreased by 6 each, then what is the average of the numbers, so obtained?

49.5

Let total numbers = 4

Sum of 4 numbers = 4 × 48 = 192

Increment in 75% by 4 each , Total increment  = 3 × 4 = 12

Decrement in 25% by 6 each , Total decrement = 1 × 6 = 6

Overall  change = 12 - 6 = 6

New average = \(\frac{192 + 6}{4}\) = \(\frac{198}{4}\)

= 49.5