Question

Вычислите используя свойства арифметических действий

а) 4 * 1/3 + 4 * 2/5 + 4 * 2/15; б) 7* 2/3 + 7 * 1/2 + 7 * 5/6

Answer 1

а) 4 * 1/3 + 4 * 2/5 + 4 * 2/15; = 4 * (1/3 + 2/5 + 2/15) = 4 * (5/15 + 6/15 + 2/15) = 4 * 13/15 = 52/15 = 3 7/15

б) 7* 2/3 + 7 * 1/2 + 7 * 5/6 = 7 * (2/3 + 1/2 + 5/6) = 7 * (4/6 + 3/6 + 5/6) = 7 * 12/6 = 7 * 2 = 14