Question

81. найдете неизвестный член пропорции (сделайте на листочке чтобы знать как правильно писать)

Answer 1

$1) \: x \div \frac{8}{9} = 3 \div 4 \\ 4x = \frac{8}{9} \times 3 \\4x = \frac{8}{3} \\ 4x = \frac{8}{3} \div 4 \\ x = \frac{2}{3}$

$2) x \div 2.8 = 5 \div 7 \\ 7x = 5 \times 2.8 \\ 7x = 14 \\ x = 2$

$3)12 \div 7 = 9 \div x \\ 12x = 7 \times 9 \\ 12x = 63 \\ x = 63 \div 12 \\ x = 5.25$

$4)6.5 \div 5.2 = x \div 8 \\ 5.2x = 6.5 \times 8 \\ 5.2x = 52 \\ x = 52 \div 5.2 \\ x = 10$

$5)4.5 \div 3.6 = x \div 4 \\ 3.6x = 45 \times 4 \\ 3.6x = 18 \\ x = 18 \div 3.6 \\ x = 5$

$6)15 \div 4 = x 1 \frac{1}{3} \\ 4x = 15 \times \frac{4}{3} \\ 4x = 20 \\ x = 20 \div 4 \\ x = 5$