Question

If X is the mean of the first 8 positive integral multiples of 9 and Y is the median of the same numbers, find the value of 5X-3Y.​

Answer 1

First 8 Multiple of 9 are :-

9 , 18 , 27 , 36 , 45 , 54 , 63 , 72

Mean = Sum of Observation/No.of observation

$=>\sf{\dfrac{9+18+27+36+45+54+63+75}{8}}$

$=>\sf{\dfrac{324}{8}}$

X = 40.5

Now ,

Median = Middle most term

$=>\sf{\dfrac{36+45}{2}}$

$=>\sf{\dfrac{81}{2}}$

Y = 40.5

Therefore,

→ 5X - 3Y

→ 5(40.5) - 3(40.5)

→ 202.5 - 121.5

→ 81 Ans...