Answer and Step-by-step explanation:
So for this question, we need to create an equation. We will use one of the most common forms of equations of math, which would be the linear equation of y=mx+b. The only difference is, we need to change the = to a ≥ symbol, meaning greater than or equal to, because the 100 dollars needs to be more or equal to the amount spent. But we cannot solve this problem until we know where everything goes.
So, the 100 is all she can spend, so this is where the ≤ comes in handy. She can use less than or equal to the amount of 100 dollars for the food for this party. And because she started out with 19 dollars, that can be added into the problem. So far we have:
100 ≥ __x + 19.
Now we need to find what the missing part of the equation is. But first let's change the x to p in this equation so that it is easier to understand. The p stands for the amount of pizzas purchased. Each pizza costs 7 dollars, so the equation should look like this:
100 ≥ 7p + 19. Now we solve for p.
-19 - 19 Subtract 19 from both sides to cancel out the positive 19 (+ 19).
81 ≥ 7p Divide 7 into 81 to single out p.
7 7 So p = 81/7. But we can't have 81/7 of a pizza, so we convert this to a decimal then round. So: 11.57142857… is the decimal form.
Now we need to round, because that is way too big. So, we round to the nearest whole number. So we look at the placement behind it (The tenths placement in this situation). Because the placement behind it (5) is on the 5 - 9 scale, the placement before it gets rounded up.
So, Ava can buy 12 pizzas.
I hope that this helps.