First one
P (L or D) = P(L) + P(D) - P(L and D) =
(18/50) + (20/50) - (6/50) =
[ 18 + 20 - 6 ] / 50 =
32/50 = 16/25 = 64%
Second one
P ( A or B ) = P (A) + P (B) - P (A and B) =
.40 + .25 - .16 =
.49
Last one
P (S or R) = P(S) + P(R) - P(S and R )
65/200 = P(S) + 5/200 - 30/200
65/100 = P(S) - 25/200 add 65/200 to both sides
90 /200 = P (S) = 9/20