A = 34/7.13 + 51/13.22 + 85/22.37 + 68/37.49 B = 39/7.16 + 65/16.31 + 52/31.43 + 26/43.49 C = 40/31.39 + 35/39.46+ 30/46.52+ 25/52.57+ 20/57.61

Đáp án:

`A=34/49`

`B=26/49`

`C=300/61`

Giải thích các bước giải:

`A=34/7.13 +51/13.22 +85/22.37+68/37.39`

`A=17(2/7.13+3/13.22+5/22.37+4/37.49)`

`A=17/3.(6/7.13+9/13.22+15/22.37+12/37.49)`

`A= 17/3.(1/7-1/13+1/13-1/22+1/22-1/37+1/37-1/49)`

`A=17/3.(1/7-1/49)`

`A=17/3. 6/49`

`A=34/49`

`B=13.(3/7.16+5/16.31+4/41.43+2/43.49)`

`B=13/3.(9/7.16+15/16.31+12/31.43+6/43.49)`

`B=13/3.(1/7-1/16+1/16-1/31+1/31-1/43+1/43-1/49)`

`B=13/3.(1/7-1/49)`

`B=13/3. 6/49`

`B=26/49`

`C=5(8/31.39+7/39.46+6/46.52+5/52.57+4/57.61)`

`C=5(1/1-1/39+1/39-1/46+1/46-1/52+1/52-1/57+1/57-1/61)`

`C=5.(1/1-1/61)`

`C=5.(60/61)`

`C=300/61`