`A=( 3 - 1/4 + 2/3 - (5 + 1/3 - 6/5 ) - (6- 7/4 +3/2)`
`A= 3 - 1/4 + 2/3 - 5 - 1/3 + 6/5 - 6 + 7/4 - 3/2`
`A= (3 - 5 - 6 ) + (-1/4 + 7/4 ) + ( 2/3 -1/3 ) + 6/5`
`A= -8 + 2/3 + 1/3 + 6/5`
`A=-8 + 1 + 6/5`
`A=-29/5`
`B=1/3 - 3/4 + 3/5 + 1/64 -2/9 -1/36 +1/15`
`B=(1/3 - 2/9) + (-3/4 + 1/36) +(3/5 +1/15) +1/64`
`B= 1/9 - 13/18 + 2/3 +1/64`
`B= 2/18 - 13/18 + 12/18 +1/64`
`B=1/18 + 1/64`
`B=41/576`
`C=1/3-3/5+5/7-7/9+9/11-11/13+13/15+11/13-9/11+7/9-5/8+3/5-1/3`
`C=(1/3-1/3)+(-3/5+3/5)+(5/7-5/7)+(-7/9+7/9)+(-11/13+11/13)+13/15`
`C=13/15`
`D=1/99 -(1/1.2 + 1/2.3 + .....+ 1/98.99)`
`D=1/99-(1/1-1/2+1/2-1/3+...+1/98-1/99)`
`D=1/99-(1/1-1/99)`
`D=1/99 - 98/99`
`D=-97/99`