Question

Aflati termenul necunoscut din proportiile:a)x/3=15/12 b) x+3/x+1=12/10​

Answer 1

$a) \frac{x}{3} = \frac{15}{12} \\ 12x = 15 \times 3 \\ 12x = 45 \\ x = \frac{45}{12} = \frac{15}{4} = 3.7$

$b) \frac{x + 3}{x + 1} = \frac{12}{10} \\ 10(x + 3) = 12(x + 1) \\ 10x + 30 = 12x + 12 \\ - 2x = - 18 \\ x = \frac{ - 18}{ - 2} = 9$