Lati needs to purchase drinks and snacks for a party. Each drink costs $0.75. Each snack costs $3.28. There is a 7% sales tax on her total purchase. She purchases an equal number of snacks and drinks. How many of each item can Lati purchase if she has $64 dollars to spend?
Let's say the number of drinks Lati buys is x and the number of snacks she buys is y: (1) x = y (2) 1.07(0.75x + 3.28y) = 64 (The 1.07 is equivalent to 107%, since she is charged an extra 7% of the total price)
Now substituting (1) into (2) we get: 1.07(0.75x + 3.28x) = 64 1.07*4.03x = 64 4.3121x = 64 x = 64/4.3121 = 14 (rounded down, since she cannot spent more than $64) Thus she can purchase 14 snacks and 14 drinks
