Question

Mihai a cheltuit o suma de bani in dua zile. In prima zi Mihai a cheltuit 30% din suma, iar in a doua zi restul de 35 de lei. Calculati suma de bani cheltuita de Mihai in prima zi.
Multumesc anticipat!

Answer 1

$x-suma \ initiala \\\\ 30\% \ din \ x \to \frac{\not 30}{\not 100}* x= \frac{3}{10}*x \longrightarrow \frac{3x}{10} - cat \ a \ cheltuit \ prima \ zi \\\\ x^{(10} -\frac{3x}{10} = \frac{10x-3x}{10} \to \frac{7x}{10} -restul \\\\\\ \frac{7x}{10}=35 \\\\ x=\frac{10* \not 35}{\not 7} \\\\ x=10*5 \\\\ \boxed{x=50 \ lei } \\\\ \frac{3* \not 50}{\not 10} = 3*5 \to 15 \ lei - a \ cheltuit \ prima \ zi$

Answer 2

SUMA INTREAGA ESTE 100%
100% - 30% = 70%
70% REPREZINTA 35 LEI - CAT A CHELTUIT A DOUA ZI
70%...........35 LEI
30%.............X
X = 30 * 35 : 70
X = 15 LEI A CHELTUIT IN PRIMA ZI