Can some one explain in an easy way pls

What needs to be done first is to add up females and males that have passed.

42 + 14 = 56

so out of 56 students who passed 42 females passed 42/56 = 3/4 = 0.75

out of 56 students who passed, 14 males passed which turns into 14/56 = 1/4 = 0.25

check work; 0.75 + 0.25 = 1.00

NOW WE ARE DOING FAILS.

15 + 5 = 20

so out of 20 students who failed, 15 females failed so it turns into 15/20 = 3/4 = 0.75

out of 20 students who failed, 5 males failed. 5/20 = 1/4 = 0.25

check work; 0.75 + 0.25 = 1.00

i hope this helped! :)