Question

Допоможіть будь ласка!​

Answer 1

Объяснение:

$1) \: 12 \div x = 4 \div 5 \\ 12 \times 5 = x \times 4 \\ 60 = 4x \\ 4x = 60 \\ x = \frac{60}{4} \\ x = 15$

$2) \: 5 \div 8 = 15 \div y \\ 5 \times y = 8 \times 15 \\ 5y = 120 \\ y = \frac{120}{5} \\ y = 24$

$3) \: 8 \div 3 = 16 \div z \\ 8 \times z = 3 \times 16 \\ 8z = 48 \\ z = \frac{48}{8} \\ z = 6$

$4) \: 2.4 \div x = 0.8 \div 5 \\ 2.4 \times 5 = x \times 0.8 \\ 12 = 0.8x \\ 0.8x = 12 \\ x = \frac{12}{0.8} \\ x = 15$

$5) \: 0.8 \div y = 2 \div 1 \frac{1}{4} \\ 0.8 \times 1 \frac{1}{4} = y \times 2 \\ 2y = 0.8 \times 1.25 \\ 2y = 1 \\ y = \frac{1}{2} \\ y = 0.5$

$6) \: z \div 4.2 = 9 \div 10.8 \\ z \times 10.8 = 4.2 \times 9 \\ 10.8z = 37.8 \\ z = \frac{37.8}{10.8} \\ z = 3.5$

$7) \: \frac{x}{7} = \frac{0.5}{0.3} \\ x \times 0.3 = 7 \times 0.5 \\ 0.3x = 3.5 \\ x = \frac{3.5}{0.3} \\ x = 11 \frac{2}{3}$

$8) \: \frac{48}{5.1} = \frac{y}{3.4} \\ 48 \times 3.4 = 5.1 \times y \\ 163.2 = 5.1y \\ 5.1y = 163.2 \\ y = \frac{163.2}{5.1} \\ y = 32$

$9) \: \frac{12}{0.5} = \frac{80}{z} \\ 12 \times z = 0.5 \times 80 \\ 12z = 40 \\ z = \frac{40}{12} \\ z = 3 \frac{1}{3}$

$10) \: \frac{x}{1.8} = \frac{1}{0.3} \\ x \times 0.3 = 1.8 \times 1 \\ 0.3x = 1.8 \\ x = \frac{1.8}{0.3} \\ x = 6$

$11) \: \frac{0.7}{y} = \frac{2.1}{33} \\ 0.7 \times 33 = y \times 2.1 \\ 23.1 = 2.1y \\ 2.1y = 23.1 \\ y = \frac{23.1}{2.1} \\ y = 11$

$12) \: \frac{0.4}{7} = \frac{z}{4.2} \\ 0.4 \times 4.2 = 7 \times z \\ 1.68 = 7z \\ 7z = 1.68 \\ z = \frac{1.68}{7} \\ z = 0.24$