A fruit stand sells 6 oranges for $3.00 and 3 grapefruit for 3.60. Kenny buys 10 oranges and 11 grapefruit. How many much does kenny spend on the fruit?

Kenny spends $21.50 on fruit

6 oranges = 3 dollars

divide both sides by 6 to get $0.50

3 grapefruits = $3.60

divide both sides by 3 to get $1.50

multiply the $0.50 by the amount of oranges Kenny buys

multiply the $1.50 by the amount of grapefruits Kenny buys

add the two amounts to get the final amount of money Kenny spent on fruit