Question

The four natural numbers x 2x 3x & 4x are such that their mean is 90. Then the numbers are:-
a) 2 4 6 8
b)9 18 27 36
c) 5 10 15 20
d) 36 72 108 144

Answer 1

Answer is option D.

mean = (x+2x+3x+4x)/4
= 10x/4


given mean = 90

90= 10x/4

90×4 = 10x
x = 9×4
= 36


mean= (36+72+108+144)/4
= 90