A. X+Y=50 y=x+20
B. 50-x=x+20 x=15 minutes
C. No, We know however much time Ted spends on the butterfly he spends 20 mins more on breast stroke. If he spends 45 mins on butterfly then he must spend 45+20= 65 mins on breast stroke. BUT we already know that he only spends 50 mins total, so it’s not possible
Upper half of the data: 81 lower half of the data: 98
62 . is 72 I don't know 61