Explicación paso a paso:
[tex]8 \: conchas = 30 \\ \\ 25 \: bolillos = 62.5 \\ \\ 7 \: donas = 31.5 \\ \\ 13 \: tambores = 49.4[/tex]
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[tex]3.75 \times 8 = 30 \\ \\ \\ 2.5 \times 25 = 62.5 \\ \\ \\ 4.5 \times 7 = 31.5 \\ \\ \\ 3.80 \times 13 = 49.4 [/tex]