2 1/3 * 3,5 = 3 1/3 * х
7/3 * 7/2 = 10/3 * х
49/6 = 10/3 * х
х = 49/6 : 10/3
х = 49/6 * 3/10 = (49*1)/(2*10) = 49/20
х = 2 целых 9/20
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Проверка:
7/3 * 7/2 = 10/3 * 49/20
49/6 = 490/60
8,1(6) = 8,1(6)
Пояснения:
2 1/3 = (2*3+1)/3 = 7/3
3,5 = 3 5/10 = 3 1/2 = (3*2+1)/2 = 7/2
3 1/3 = (3*3+1)/3 = 10/3