Question

O masina a parcurs o distanta in 3 zile astfel:in prima zi a parcurs $\frac{7}{20}$ din drum,a doua zi a parcurs $\frac{1}{5}$ din distanta ramasa,iar a treia zi a parcurs restul de 624 km.
a)Cati km are intreaga distanta?
b) Cati km a parcurs a doua zi?

Answer 1

4x/5=624
x=780 in a doua si a treia zi
780 reprezinta 13/20 adica a doua zi
13y/20=780
y=1200 km tot drumul

Answer 2

x=distanta
$\frac{7}{20}*x=$Prima zi
$\frac{13}{20}*x* \frac{1}{5}= \frac{13}{100}*x$=A DOUA ZI
A treia zi = restul de 624 km
⇒$x-(\frac{7x}{20}+ \frac{13x}{100})=x-(\frac{35x+13}{100})x- \frac{48x}{100}= \frac{52x}{100}$
$\frac{52x}{100}=624$
x=$\frac{624*100}{52}=1200 km$

Prima zi =$\frac{7}{20}*1200= \frac{1200}{20}*7=60*7=420$
1200-420=780.
$\frac{1}{5}*780=780:5=156$(a doua zi)