Answer:
10 days to complete
Step-by-step explanation:
for mixed rate problems, the sum of each individual reciprocal rates equals the sum of the combined rate
i.e
we are given,
A's rate = 15 days to complete
Combined rate = 6 days to complete
B's rate = need to find
substituting' the given info into the equation above,
1/15 + 1/ (B's Rate) = 1/6
1 / (B's Rate) = 1/6 - 1/15 (convert right side to same denominator)
1 / (B's Rate) = 5/30 - 2/30
1 / (B's Rate) = 3/30
1 / (B's Rate) = 1/10 (taking reciprocal of both sides)
B's rate = 10 days to complete