Para somar $\mathbf{\frac{\textcolor{#ef4444}{1}}{\textcolor{#3b82f6}{2}}}$ com $\mathbf{\frac{\textcolor{#ef4444}{1}}{\textcolor{#3b82f6}{3}}}$ na fita, é preciso medir as duas nos mesmos pedaços em que ela está partida: sextos. A fita tem 6 partes iguais, e o 6 serve de denominador comum, pois está na tabuada do 2 e na do 3.

Metade da fita são 3 partes, porque:

$\mathbf{\dfrac{\textcolor{#ef4444}{1}}{\textcolor{#3b82f6}{2}}}$

= $\mathbf{\dfrac{\textcolor{#ef4444}{1} \times 3}{\textcolor{#3b82f6}{2} \times 3}}$

= $\mathbf{\dfrac{\textcolor{#ef4444}{3}}{\textcolor{#3b82f6}{6}}}$

E um terço da fita são 2 partes, porque:

$\mathbf{\dfrac{\textcolor{#ef4444}{1}}{\textcolor{#3b82f6}{3}}}$

= $\mathbf{\dfrac{\textcolor{#ef4444}{1} \times 2}{\textcolor{#3b82f6}{3} \times 2}}$

= $\mathbf{\dfrac{\textcolor{#ef4444}{2}}{\textcolor{#3b82f6}{6}}}$

Somando as partes de cima, no mesmo tamanho:

$\mathbf{\dfrac{\textcolor{#ef4444}{3}}{\textcolor{#3b82f6}{6}} + \dfrac{\textcolor{#ef4444}{2}}{\textcolor{#3b82f6}{6}}}$

= $\mathbf{\dfrac{\textcolor{#ef4444}{5}}{\textcolor{#3b82f6}{6}}}$

A soma vale $\mathbf{\frac{\textcolor{#ef4444}{5}}{\textcolor{#3b82f6}{6}}}$ da fita, ou seja, 5 das 6 partes. Como as seis partes são todas iguais, tanto faz quais cinco pintar: o que importa é a quantidade.

Resposta: pintar quaisquer 5 das 6 partes.

Questão Q14845