NIELIT 2022 Feb Scientist D - Section D: 20

Question

The sum of the seven numbers is $254.$ The average of first three is $25$ and that of the last three is $44.$ The fourth number is :

• A. $40$
• B. $47$
• C. $45$
• D. $48$

Answer 1

Assume that $7$ number’s are $a,b,c,d,e,f,g$.Now according to the given information:

• $a+b+c+d+e+f+g=254….(i)$
• $a+b+c=25\times 3=75….(ii)$
• $e+f+g=44\times3=132...(iii)$

substitute (ii),(iii) to (i),we get: $75+d+132=254\implies d=254-207=47$

Option (B) is correct.