a, 1 - 2/(3 . 5) - 2/(5 . 7) - 2/(7 . 9) - ... - 2/(61 . 63) - 2/(63 . 65)
= 1 - (2/(3 . 5) + 2/(5 . 7) + 2/(7 . 9) + ... + 2/(61 . 63) +  2/(63 . 65))
= 1 - (1/3 - 1/5 + 1/5 - 1/7 + ... + 1/63 - 1/65)
= 1 - (1/3 - 1/65)
= 1 - (65/195 - 3/195)
= 195/195 - 62/195
= 133/195
b, 1/2 + 5/6 + 11/12 + 19/20 + 29/30 + 41/42 + 55/56 + 71/72 + 89/90
= (1 - 1/2) + (1 - 1/6) + (1 - 1/12) + (1- 1/20) + (1 - 1/30) + (1 - 1/42) +(1 - 1/56) + (1 - 1/72) + (1 - 1/90)
= 1 - 1/2 + 1 - 1/6 + 1 - 1/12 + 1 - 1/20 + 1 - 1/30 + 1 - 1/42 + 1 - 1/56 + 1 - 1/72 + 1 - 1/90
= ( 1  + 1 + 1 + 1 +1 + 1 +1 +1 +1) -( 1/2  + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56 + 1/72 + 1/90)
= 9 - (1/( 1 . 2) + 1/(2 . 3) + 1/(3 . 4) + 1/(4 . 5) + 1/(5 . 6) + 1/(6 . 7) + 1/(7 . 8) + 1/(8 . 9) + 1/(9 . 10))
= 9 - (1 - 1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10)
= 9 - (1 - 1/10)
= 90/10 - 9/10 
= 81/10

x-1/5=-3/2 x=-3/2+1/5 x=-15/10+2/10=-13/10
-3/11-(x-2/5)=-14/22 x=-3/11+14/22=-6/22+14/22=5/22