AP ICET 2016 Paper

Given observations : 7, 10, 13, 16, ......., 121
The above observation are in A.P and σ is their S.D.
    7, 10, 13, 16,......‌‌121
(×7+1)‌↓ ‌↓ ‌‌‌‌↓ ‌‌‌↓  ‌‌‌‌↓
    50,‌‌71, ‌92, 113......‌848
The second set of observations is obtained by multiplying observations of the first set by 7 and adding 1 to the product.
∴Required S.D of (50, 71, 92, 113, ........, 848) = 7σ