What is 90% of 50?
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This is so hard and it’s for a test

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible

Susie wants to take her friend out for lunch.she wants to spend $9.75 each person. how much will she spend in all.