Sagot :
Answer:
It takes Jane 7.5 hours alone
Step-by-step explanation:
x hours = Jane's rate
5 hours = Maricris's rate
Maricris does 1/5 of the job in one hour and Jane does 1/x of the job in one hour.
(1/x)(3) + (1/5)(3) = 1
(3/x) + (3/5) = 1
Multiply both sides by 5x
15 + 3x = 5x
15 = 5x - 3x
15 = 2x
x = 7.5 hours is Jane's rate