Question

Calculati:
a)3:2/5
b)5:3/4
c)8:1/2
d)2:3 1/2
e)5/3:4
f)8/7:6
g)1/3:3
h)2 3/2:2

Answer 1

Ce trebuie să știm pentru a putea rezolva?

$\red{ \boxed{ \bf\green{a = \frac{a}{1} }}}$

$\red{ \boxed{ \bold{ \green{\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c} }}}}$

La împărțirea a doua fracții o înmulțim pe prima cu a doua inversată.

Rezolvare:

a)

$3 \div \frac{2}{5} = 3 \times \frac{5}{2} = \\ \\ = \frac{3 \times 5}{2} = \frac{15}{2}$

b)

$5 \div \frac{3}{4} = 5 \times \frac{4}{3} = \\ \\ = \frac{5 \times 4}{3} = \frac{20}{3}$

c)

$= 8 \div \frac{1}{2} = 8 \times \frac{2}{1} = 8 \times 2 = \\ = 16$

d)

$2 \div 3 \frac{1}{2} = 2 \div \frac{7}{2} = 2 \times \frac{2}{7} = \\ \\ = \frac{2 \times 2}{7} = \frac{4}{7}$

e)

$\frac{5}{3} \div 4 = \frac{5}{3} \div \frac{4}{1} = \frac{5}{3} \times \frac{1}{4} = \\ \\ = \frac{5 \times 1}{3 \times 4} = \frac{5}{12}$

f)

$\frac{8}{7} \div 6 = \frac{8}{7} \div \frac{6}{1} = \frac{8}{7} \times \frac{1}{6} = \\ \\ = \frac{8 \times 1}{7 \times 6} = \frac{8}{42}$

g)

$\frac{1}{3} \div 3 = \frac{1}{3} \div \frac{3}{1} = \frac{1}{3} \times \frac{1}{3} = \\ \\ = \frac{1 \times 1}{3 \times 3} = \frac{1}{9}$

h)

$2 \frac{3}{2} \div 2 = \frac{7}{2} \div \frac{2}{1} = \frac{7}{2} \times \frac{1}{2} = \\ \\ = \frac{7 \times 1}{2 \times 2} = \frac{7}{4}$