let's convert the 2 and 1/2 to "improper", and let's keep in mind that 0.75 is just 3/4.
so, what is .75 of 2 and 1/2? well is just their product,
[tex]\bf \stackrel{mixed}{2\frac{1}{2}}\implies \cfrac{2\cdot 2+1}{2}\implies \stackrel{improper}{\cfrac{5}{2}}
\qquad \qquad \qquad
0.75\implies \cfrac{075}{100}\implies \cfrac{3}{4}\\\\
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\cfrac{5}{2}\cdot \cfrac{3}{4}\implies \cfrac{15}{8}
[/tex]
[tex]\bf \textit{5 family members, thus, how many times does 5 go into }\frac{15}{8}?
\\\\\\
\cfrac{\quad \frac{15}{8}\quad }{5}\implies \cfrac{\quad \frac{15}{8}\quad }{\frac{5}{1}}\implies \cfrac{15}{8}\cdot \cfrac{1}{5}\implies \cfrac{3}{8}\implies 0.375[/tex]
