To solve this you need to figure out how many cakes mark can make a day so to do this you divide 4242 by 77 and get 55.09090909 (repeating) so for this lets just round up to 55.1 now all you got to do is multiply 55.1 * 55 and you get 3030.50. so mark can make approximately 3030.5 cakes in 55 days
'Mark can make 42 birthday cakes in 7 days. How many birthday cakes can Mark make in 5 days?'
ratio and proprtion
times both sides by 5
555 times 546 equals to 303,030.