Suppose you buy lunch for the math club. you have enough money to buy 20 salads or 15 sandwiches. the group wants 12 sandwiches. How many salads can you buy?

Question

need to figure out this. 

Answer 1

Hi Shaquana, 

 

There's a few ways to solve this question. We know that if we spend all of the money, we can buy 15 sandwiches. The group wants 12 sandwiches, so if we do purchase the desired 12, we are using up 12/15 = 4/5 = 80% of the budget. That means that there is 20% of our budget leftover, which means we can buy 20% * 20 = 4 salads. 

 

Another, and possibly easier way to think about this question, is to create an actual budget and plug in numbers. To make things simple, try to find a common multiple of 20 and 15...in this case lets assume your total budget is $120 (you can pick any number here). Since we are told that we can purchase 20 salads with all of our budget, that means each salad costs 120/20 = $6. Since we are told we can purchase 15 sandwiches with the total budget, we know each sandwich costs 120/15 = $8. With this information,we can now solve the problem: if 12 sandwiches are purchased, we are spending 12*8 = $96. That leaves 120 - 96 = $24 leftover, which would purchase 24/6 = 4 salads.