Select the missing number ?
6     7   21
8     6    24
12    9   ?

Options

A. 54
B. 60
C. 18
D. 27

Answer

A

Explanation

The pattern followed here is,
`(6 xx 7) //2 = 21`,
`(8 xx 6) //2 = 24`,
`(12 xx 9) //2 = 54`.