Gina has 500 minutes of talk time on her cellphone. She uses 30 minutes every time she makes a call. Write an equation describing the amount of minutes remaining on her phone, m, and the number of calls made, c.

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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?