Вычеслите 2/5 *(3/8 - 1/5)
1) 3/8 - 1/5 = 15-8/40 = 7/40 2) 7/40 × 2/5 = 7·2/40·5 = 14/200 = 7·2/100·2 = 7/100 = 0.07