[tex]\bf \textit{hmm how much is 0.25 of the pizzas?}\quad 0.25\cdot 40\implies \boxed{10}\leftarrow Ronnie
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\textit{we know Mack stacked only \boxed{9}}
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\textit{what is the 35\% of 40?}\quad \left(\frac{35}{100} \right)\cdot 40\implies \boxed{14}\leftarrow Kim
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\textit{how many remain?}\quad 40-(10+9+14)\implies \boxed{7}\leftarrow Ada[/tex]
so.. that's how many each did, surely you'd know who did the most pizzas.