Question

Let a, b be any two real numbers and a*b=a.b/3 then (7*3)*9= ?
A, 21
B, 63
C, 27
D, 33

Answer 1

a and b be any two real numbers such that a*b = a.b/3

we have to find the value of (7*3)*9 = ?

first find 7*3
from question, a*b = a.b/3
so, 7*3 = 7.3/3 = 7

now, (7*3)*9 = 7*9
again, 7*9 = 7.9/3 [ from question ]
= 7.3 = 21

hence , (7*3)*9 = 21

therefore, option (A) is correct.

Answer 2

a and b be any two real numbers such that a*b = a.b/3

we have to find the value of (7*3)*9 = ?

first we will find 7*3

from question, a*b = a.b/3

so,

7*3 = 7.3/3 = 7

now, (7*3)*9 = 7*9

again, 7*9 = 7.9/3 [ from question ]

= 7.3 = 21

hence , (7*3)*9 = 21

therefore, option (A) is correct.