Question

Jernai can complete her algebra 1 final project in 4 hours. Recently she was under a tight deadline, so she and daniela worked together to complete the project in 2.4 hours. How many hours would it take daniela to complete the project on her own ?

Answer 1

6 hours

Explanation:

We have that the speed in this case would be given per project / hour

Which means, that the speed of Jernai would be:

1/4 project / hour and also that the speed of the two meetings would be 1 / 2.4 project / hour, we know that this result must give more the sum of daniela's speed, therefore:

1/4 + 1 / x = 1 / 2.4

where x is the time in hours that daniela takes:

1 / x = 1 / 2.4 - 1/4

1 / x = 0.1666

x = 1 / 0.1666

x = 6

Which means that Daniela takes 6 hours to do her project if she does it alone