Пошаговое объяснение:
1,2÷x=1 1/3÷1 3/7
1 1/3 * x = 1,2 * 1 3/7
1 1/3* x = 6/5 * 10/7
1 1/3 * x = 12/7
x = 12/7 : 1 1/3
x = 12/7 * 3/4
x = 9/7
x = 1 2/7
