81/88×(6-1 13/15×1 19/21)= плиззз помогите

Question

81/88×(6-1 13/15×1 19/21)= плиззз помогите

Answer 1

81/88 * (6 - 1 13/15 * 1 19/21) = 2 целых 1/4

1) 1 13/15 * 1 19/21 = 28/15 * 40/21 = (4*8)/(3*3) = 32/9
2) 6 - 32/9 = 54/9 - 32/9 = 22/9
3) 81/88 * 22/9 = (9*2)/(8*1) = 18/8 = 2 2/8 = 2 1/4