Since the numbers are in % form,let’s assume that the total base size of students is 100
Arranging them into table form,as calculation will be easier
Male Female Total
< 25 years old
29 42 71
>= 25 years old
(40/100)*48 = 19 (20/100)*52 =10 29
Total
48 52 100
Probability = Favourable possibilities/Total possibilities
= (29+42)/100
= (71)/100 = 0.71
Arranging them into table form,as calculation will be easier
Male Female Total
< 25 years old
29 42 71
>= 25 years old
(40/100)*48 = 19 (20/100)*52 =10 29
Total
48 52 100
Probability = Favourable possibilities/Total possibilities
= (29+42)/100
= (71)/100 = 0.71