Question

daca 20% dintr-un nr este 15, atunci numarul este?

Answer 1

20% ,,,,,,,,,,,,,,,,,,,,15

100% ,,,,,,,,,,,,,,,,,,, y ( numarul)

y = 100 x 15 : 20 = 1500: 20 = 75

numarul este 75

verificare : 20% din 75 = 75 x 20 : 100 = 15

Answer 2

$\it Not\breve{a}m\ num\breve{a}rul\ cerut\ cu \ x.\\ \\ 20\%\ din\ x =15 \Rightarrow \dfrac{20}{100} \cdot x = 15 \Rightarrow x = 15\cdot\dfrac{100}{20} = 15\cdot5=75$