Question
Frank and Hank are farmers. Frank can plant a field in 3 hours, but when he works with Hank, they
can plant a field in 1 hour. How long, in minutes, would it take Hank to plant a field by himself?
can plant a field in 1 hour. How long, in minutes, would it take Hank to plant a field by himself?
Answers
Reiny
franks rate = 1/3
Hanks rate = 1/x
combined rate = 1/3 + 1/x
= (x+3)/(3x)
1/( (x+3)/(3x) ) = 1
3x/(x+3) = 1
3x = x + 3
2x = 3
x = 1.5
It would take him 1.5 hours
Hanks rate = 1/x
combined rate = 1/3 + 1/x
= (x+3)/(3x)
1/( (x+3)/(3x) ) = 1
3x/(x+3) = 1
3x = x + 3
2x = 3
x = 1.5
It would take him 1.5 hours
cool1stgrader
1st grade or waht