All you have to do to solve this problem is to put it into fraction form: if for every $4 Jo makes, Leila makes $3, then the fraction would be 3/4.
To solve this divide 60 by 4 to get 15 and then multiply 15 by 3 to get Leila's pay. 15*3=45
Check it by putting it into simplest form as a fraction to see if it checks:
45/60=3/4 and 3/4=3/4 so therefore Leila makes $45 in profit