Big sale at the mall this weekend! Tank tops are on clearance for 70% off. T-shirts that regularly cost $20.00 are on sale for $12.00 each if you buy 3 or more. All jeans are half off. Write an equation to calculate the total cost of 2 tank tops, 3 T-shirts, and 1 pair of jeans. Use t to represent the original price of a tank top and j to represent the original price of a pair of jeans.