- 10,125 * 3 1/3 + (-8,75) * 2 4/7 = - 56 целых 1/4 = - 56,25
1 способ (в обыкновенных дробях)
1) - 10,125 * 3 1/3 = - 10 1/8 * 3 1/3 = - 81/8 * 10/3 = - (27*5)/(4*1) = - 135/4 = - 33 целых 3/4
2) - 8,75 * 2 4/7 = - 8 3/4 * 2 4/7 = - 35/4 * 18/7 = - (5*9)/(2*1) = - 45/2 = - 22 целых 1/2
3) - 33 3/4 + (-22 1/2) = - (33 3/4 + 22 2/4) = - 55 5/4 = - 56 1/4
2 способ (в десятичных дробях)
1) - 10,125 * 3 1/3 = - 10,125 * 10/3 = - 10,125 * 10 : 3 = - 33,75
2) - 8,75 * 2 4/7 = - 8,75 * 18/7 = - 8,75 * 18 : 7 = - 22,5
3) - 33,75 + (-22,5) = - (33,75 + 22,5) = - 56,25
Пояснения:
0,125 = 125/100 = 1/8 - сократили на 125
3 целых 1/3 = (3*3+1)/3 = 10/3
0,75 = 75/100 = 3/4 - сократили на 25
2 целых 4/7 = (2*7+4)/7 = 18/7