`{:(7,8,6),(6,5,9),(12,13,?),(504,520,486):}`

Options

A. 7
B. 12
C. 8
D. 9

Answer

D

Explanation

`7 xx 6 xx 12 = 504`
`8 xx 5 xx 13= 520`
`6 xx 9 xx ? = 486`
`:. ? = (486)/(9 xx 6)= 9`