how came 0.15?

how this question can be solved?

9. If 4 x 5 = 1620, 3 x 8 = 924 then 7 x 6 =?

A. 1740
B. 1880
C. 4949
D. 4942

ans D

ALSO SOLVE SAMPLE PAPER QUESTIONS


5. A coffee shop sold 35 cups of coffee. Of these, 15 contained sugar and 12 contained milk. If 13 cups contained neither milk nor sugar, how many cups must have contained both sugar and milk?

A. 3
B. 5
C. 7
D. 8
E. 12

6. If 3/p = 6 and 3/q = 15 then p - q =?

A. 1/3
B. 2/5
C. 3/10
D. 5/6
E. None of the above


SOLVE PLEASE