work rate

[mariah]

At their respective rates, machine A produced 6000 nails and B produced 8000 nails. Is A cost more time than B?

1). B can produce 2000 more nails than A during an hour.
2). B's rate is twice that of A

oa not provided imo B

[Anurag@Gurome]

At their respective rates, machine A produced 6000 nails and B produced 8000 nails. Is A cost more time than B?

1). B can produce 2000 more nails than A during an hour.
2). B's rate is twice that of A

oa not provided imo B

(1) If machine A produces 6000 nails per hour, then B produces 8000 nails per hour. Here they are taking the same time.
If machine A produces 100 nails per hour, then B produces 2100 nails per hour. Here A will take more time than B; NOT sufficient.

(2) B's rate is twice that of A implies if machine A produces 6000 nails at a certain time, then B will produce 1200 nails in that time, which means that B has already produced 8000 nails, so his job is done. So, B will take lesser time; SUFFICIENT.

The correct answer is B.