Question

Nicole can mow a large lawn in about 4 hours. When Nicole and Jessica work together, they can mow the same lawn in about 2.5 hours. How many hours would it take Jessica to mow the lawn by herself? Round to the nearest tenth.

Answer 1

`6(2)/(3)\ h`

Explanation:

step 1

we know that

Nicole can mow a large lawn in about 4 hours

That means----> In 4 hours Nicole mow the 100% of the lawn

so

using proportion

Find out what percentage Nicole mow in 2.5 hours

`(4)/(100)\ (h)/(\%)=(2.5)/(x)\ (h)/(\%)\\\\x=100(2.5)/4\\\\x= 62.5\%`

step 2

we know that

When Nicole and Jessica work together, they can mow the same lawn in about 2.5 hours

Remember that in 2.5 hours Nicole mow 62.5%

That means -----> Jessica in 2.5 hours mow 100%-62.5%=37.5%

using proportion

Find out how many hours would it take Jessica to mow the lawn (100%) by herself

`(2.5)/(37.5)\ (h)/(\%)=(x)/(100)\ (h)/(\%)`

`x=2.5(100)/37.5\\\\x=6(2)/(3)\ h`