Вычислите помогите пожалуйста г)2/5*15 д)1/4*4 е)5*1/5 г)3/7*2 1/3 д)1 1/3*1/2 б)3*5 1/4*1 1/7*5 1/2*4/11

2/5 * 15 = (2*15)/5 = 30/5=  6 1/4 * 4 = 1*4/4 = 1 5* 1/5 = 5*1 /5 = 1 3/7 * 2 1/3 = 3/7 * 7/3 3*7/7*3 = 21/21 = 1 1 1/3 * 1/2 = 4/3 * 1/2 = 4 *1 / 3* 2 = 4/6 = 2/3 б)  3 * 5 1/4 = 3 * 21/4 = 63/4       63/4 * 1 1/7 = 63/4 * 8/7 = (63 *8)/ (4*7) = 504 / 28 = 18       18 * 5 1/2 = 18 * 11/2 = 198/2        198/2 * 4/11 = (198 *4)/ 2*11 =     сокращаем 2 и 11  = 18 * 2 = 36