Question

How would I solve this?

Answer 1

For any amount of Abigail's mixture, there is a 2/3-to-3/5 ratio of walnuts to dried fruit. So if $w$ is the amount of walnuts and $f$ is the amount of fruit in the mix, we have the relationship

$\dfrac23w=\dfrac35f$

If she uses one pound of fruit, so that $f=1$, she would need

$\dfrac23w=\dfrac35\implies\dfrac32\cdot\dfrac23w=\dfrac32\cdot\dfrac35\implies w=\dfrac9{10}$

or 9/10 pound of walnuts.