Найдите значения выражения а)1/4*4/9;б)1/7*2 1/3;в)2 2/5*5/6;г)(1/5+2/15)*3/4;д)(1/2-1/3)*6

а) 1/4 * 4/9 = (1 * 4)/(4 * 9) = 1/9;б) 1/7 * 2 1/3 = 1/7 * 7/3 = (1 * 7)/(7 * 3) = 1/3;в) 2 2/5 * 5/6 = 12/5 * 5/6 = (12 * 5)/(5 * 6) = (2 * 1)/(1 * 1) = 2/1 = 2;г) (1/5 + 2/15) * 3/4 = ((3 * 1)/15 + 2/15) * 3/4 = (3/15 + 2/15) * 3/4 = 5/15 * 3/4 = 1/3 * 3/4 = (1 * 3)/(3 * 4) = 1/4 ;д) (1/2 - 1/3) * 6 = (3/6 – 2/6) * 6 = 1/6 * 6 = 6/6 = 1.