We will find that out as follows:
*We determine the cost of buying the 60 mouth guards in both cases and then subtract the smallest value from the greatest:
[tex]x=\frac{60\cdot14.50}{10}\Rightarrow x=87[/tex]&
[tex]x=\frac{60\cdot22.50}{15}\Rightarrow x=90[/tex][These calculations are respectively]
So, we can see that he would save:
[tex]s=90-87\Rightarrow s=3[/tex]So, he would save $3 in total.