Un turist merge in prima zi 30% din drum. A doua zi merge restul de 21 km. drumul are o lungime de.....km

Răspuns:

notăm x turistul

Prima zi:

[tex]x = \frac{30}{100} \times x = >x = \frac{30x}{100} [/tex]

Total

[tex] \frac{x}{1} - \frac{30x}{100} = 21 = > \frac{100x}{100} - \frac{30x}{100} = \frac{2100}{100} = > 100x - 30x = 2100 = > 70x = 2100 = > x = 2100 \div 70 = > x = 30km[/tex]

In a doua zi: x-30x/100=21