probability that chloe fails =2/5

probability of danny passing =x/y

x/y*3/5=7/15

3x/5y=7/15

3x=7

x=2.5

5y=15

y=3 probability that danny passes is 2.5/3

probability that he fails is 0.5/3

therefore the probability that they both fail

0.5/3*2/5 =1/15