Simplify Complex Rational Expressions · Exercise 46

Ironing Lenore can do the ironing for her family’s business in $h$ hours. Her daughter would take $h+2$ hours to get the ironing done. If Lenore and her daughter work together, using 2 irons, the number of hours it would take them to do all the ironing is $\frac{1}{\frac{1}{h}+\frac{1}{h+2}}$.

ⓐ Simplify the complex fraction $\frac{1}{\frac{1}{h}+\frac{1}{h+2}}$.
ⓑ Find the number of hours it would take Lenore and her daughter, working together, to get the ironing done if $h=4$.

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Elementary Algebra 2e · §8.5 Simplify Complex Rational Expressions · Exercise 46