Question

Ajutor va rog ex 3 ofer 25 de puncte

Answer 1

Notam lungimea traseului cu x

In prima zi, turistul parcurge $\bf \dfrac{1}{4}\cdot x$

In a doua zi parcurge  $\bf \dfrac{2}{5}\cdot x +14$

In a treia zi parcurge 21 km

$\bf \dfrac{1}{4}\cdot x + \dfrac{2}{5}\cdot x +14 + 21 = x$

$\bf \dfrac{x}{4} + \dfrac{2x}{5} +35 = x\:\: |\cdot 20$

$\bf 5x+8x+700=20 x$

$\bf 13x+700=20 x$

$\bf 700=20 x-13x$

$\bf 700=7 x\:\:|:7$

$\boxed{\bf x = 100\:km}$

In prima zi a parcurs 100 km : 4 ⇒ 25 km a parcurs in prima zi