Question

The average of 4 numbers is 7. If the
sum of first three numbers if 20, find
the fourth number
1) 7
3) 9
4) 8
2) 10
​

Answer 1

let the no. be x.

average = sum of numbers / no. of digits

= 20 +x/4

lol i dont know i tries my best

Answer 2

sum of first three numbers = 20

fourth number be x.

then,

= (20 + x) / 4 = 7

= 20 + x. = 7*4

= 20. +x = 28

= x. = 28- 20 = 8.

therefore,fourth number is 8 (4).

hope it helps u.