`A=1/31[31/5(9-1/2)-17/2(4+1/5)]+1/2+1/6+1/12+...+1/930`
`A=(1/1.2+1/2.3+1/3.4+...+1/30.31)+1/31[6,2(9-0,5)-8,5(4+0,2)]`
`A=(1-1/2+1/2-1/3+1/3-1/4+...+1/30-1/31)+1/31[6,2.8,5-8,5.4,2]`
`A=(1-1/31)+1/31[8,5(6,2-4,2)]`
`A=(31/31-1/31)+1/31[8,5.2]`
`A=30/31+1/31. 17`
`A=30/31+17/31`
`A=[30+17]/31`
`A=47/31`