Question

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Answer 1

3)

$\frac{x}{0.8} = \frac{15}{4} \\ 4x = 15 \times 0.8 \\ 4x = 12 \\ x = \frac{12}{4} \\ x = 3$

4)

$\frac{5 - y}{4} = \frac{3}{7} \\ 7(5 - y) = 3 \times 4 \\ 35 - 7y = 12 \\ - 7y = 12 - 35 \\ - 7y = - 23 \\ y = \frac{ 7}{ 23}$