Question

Victor are o sumă de bani

Answer 1

Răspuns:

3x/7 - a cheltuit in prima zi

⁷⁾x-3x/7=(7x-3x)/7=4x/7 rest

4x/7·1/4=x/7 a cheltuit a2a zi

3x/7+x/7+⁷⁾120=⁷⁾x

3x+x+840=7x

840=7x-4x

x=840:3

x=280 lei suma initiala

Answer 2

$\it \dfrac{3}{4}(1-\dfrac{3}{7})s=120 \Rightarrow\dfrac{3}{\not4}\cdot\dfrac{\not4}{7}s=120 \Rightarrow \dfrac{3}{7}s=120 \Rightarrow s=120\cdot\dfrac{7}{3}=40\cdot7=280$