Question

1,2,3,4 vă rog frumos ​

Answer 1

1.

$\frac{x}{5} = \frac{12}{3} \\ 5 \times 12 = 3x \\ 60 = 3x \\ x = 20$

2.

15 litri lapte. 2 kg smântână

x. litri lapte. 3 kg smântână

$x = \frac{15 \times 3}{2} \\ x = 45 \div 2 \\ x = 22.5$

x=22 litri si jumătate

3. a)

$\frac{14}{100} \times 50 = \frac{14}{10} \times 5 = \frac{14}{2} = 7$

b)

$\frac{5}{100} x = 18 \\ x = 18 \div \frac{5}{100} \\ x =18 \times \frac{100}{5} \\ x= 18 \times 20 \\ x= 18 \times 10 \times 2 \\ x = 180\times 2 \\ x = 320$

c)

$\frac{x}{100} \times 70 = 63 \\ \frac{x}{100} = \frac{63}{70} \\ \frac{x}{10} = \frac{63}{7} \\ \frac{x}{10} = 9 \\ x = 9 \times 10 \\ x = 90$

4.

6 cai. 4 zile

8 cai. x zile

$x = \frac{8 \times 4}{6} \\ x = 32 \div 6 = 5.3$

8 cai vor manca acel fan in 5 zile si cateva ore