Question

А) 6/7 : × = 6/21

Б) × : 3/7= 14/15

Answer 1

А)
6/7 ÷ х = 6/21
6/7 × 1/х = 6/21
6/7х = 6/21
42 = 14х
14х = 42
х = 42/14
х = 3

Б)
х ÷ 3/7 = 14/15
х × 7/3 = 14/15
7/3х = 14/15
х = 2/5

Answer 2

A)
$frac{6}{7} div x= frac{6}{21}$
$x = frac{6}{7} div frac{6}{21}$

$x = frac{6}{7} times frac{21}{6}$
$x = frac{6 times 21}{6 times 7}$
$x = 3$
Б)
$x div frac{3}{7} = frac{14}{15}$
$x = frac{3}{7} times frac{14}{15}$
$x = frac{3 times 14}{7 times 15}$
$x = frac{2}{5} = 0.4$