Someone please help ASAP

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

Frank has a devised a formula for his catering business that calculates the number of meatballs he needs to prepare. the formula is m=4a+2c, where c=number of children; m=number of meatballs; a=number of adults. how many meatballs are required for a party of 10 adults and 5 children?

Of the 50 us states 4 have names that start with the letter w