virtual gate 2016 pipeline

Question

There are two processor M1 and M2. M1 uses four pipeline stages with the delay of respectively stage as 6 ns, 4 ns, 7 ns, 5 ns. M2 has got 7 pipeline stages with the delay of cache stage 4 ns. Then pick the correct option for executing 200 instructions on M1 and M2.

(A) M2 is faster by 600 ns
(B) M2 is faster by 595 ns
(C) M2 is faster by 610 ns
(D) M2 is faster by 513 ns

Answer 1

for M1 = (4 + (200-1) ) *7 = 1421

M2 = (7 + (200-1) )*4 = 824

so M2 is faster by (1421- 824) = 597 ms

most near ans is  B