Question 1174114

Kevin stuffs shrimp in his job as a seafood chef. He can stuff 1,500 shrimp in 4 hours. When his sister helps him, they can stuff 1,500 shrimp in 3 hours. If Kevin gets sick, how long will it take his sister to stuff 750 shrimp?
<pre>Stuffing 1,500 is regarded as 1 JOB
Stuffing 750 is considered to be ½ of the JOB

Let time it takes the sister to do the job by herself be S
Then she can do {{{1/S}}} of job in 1 hour

Kevin can do the job by himself in 4 hours
So, he can do ¼ of job in 1 hour

Working together, they both can do the job in 3 hours, so we the get: {{{matrix(1,3, 1/S + 1/4, "=", 1/3)}}}
12 + 3S = 4S ------ Multiplying by LCD, 12S
Time it takes the sister to do the job by herself, or S = 12 hours

If she can do entire job (stuffing 1,500 shrimp) in 12 hours, then she can complete {{{highlight_green(matrix(1,12, 1/2, of, the, job, "(stuffing", 750, "shrimp)", in, (1/2)12, hours, "=", highlight(matrix(1,2, 6, hours))))}}}</pre>