Answer:
[tex]\frac{10}{3}[/tex]
Step-by-step explanation:
Let
x ----> the money Adam still has
y ---> the money Adam spent
r ---> the ratio of money he still has, to money he's spent.
[tex]r=\frac{x}{y}[/tex]
we know that
The money Adam still has is the same as the money he originally had minus the money he spent.
so
[tex]x=\$91-\$21=\$70[/tex]
we have
[tex]y=\$21[/tex]
Find the ratio
[tex]r=\frac{70}{21}[/tex]
Simplify
Divide by 7 both numerator and denominator
[tex]r=\frac{10}{3}[/tex]
