Ответ:

58.

1) = 8 1/24

2) = 649/90

3) = 1397/54

4) = 517/60

Умножение дробей:

59.

1)= 1/16×8/7=1/2×1/7= 1/14

2)=4×8/7×9=32/63

3)=56×1/77=8×1/11=8/11

4)=5/72×40/9=5/9×5/9=25/81

60.

1)=7/1×4/37=7×4/1×37=28/37

2)=7/5

3)=8×2=16

4)=27/8×7/9=3/8×7=21/8

5)=32/7×2 11/12=32/7×11/6=16/7×11/3=176/21

6)=15/13×5/8×1/7=75/728

61.

64×(3/4) =48 (км)-проедет поезд за 3/4 часа.

Ответ: 48 км

62.

1) =7/18 kp

2) =5/7 xy

3) =3 xyz

63.

1)5c/18+7/24c-11/36c=5c/18+7c/24-11c/36=4×5c/4×18+3×7c/3×24-2×11c/2×36=20c/72+21c/72-22c/72=19/72c

2)39/16y+65/20y+11/8y=39/16y+13/4y+11/8y=113/16y

:)