Question

vă rog repede plssss‍️​

Answer 1

$a) \: \frac{n}{7} = \frac{6}{21} \implies \: 3n = 6\implies n = 2 \\ \\ b) \: \frac{2}{5} = \frac{10}{n + 1} \implies n + 1 = 5 \times 5 \\ \implies n = 25 - 1\implies \: n = 24 \\ \\ c) \: \frac{9}{n} = \frac{12}{12} \implies \: n = 9$