Jack needs to raise $200 for his trip. He plans to sell cookies for $0.25 per cookie. How many cookies would he need to sell to meet his goal?

Answer 1

If we have one cookie we know that its .25. Now we can add them all up to get to 200 and keep count for each cookie. But a better way is to look at the problem in algebraic terms. Each cookie can represent the letter c.

.25 multiplied by c or .25c

We know that .25 times 1 cookie is still .25. so if c = 1 then .25c = .25. But we need the number of cookies for our 200 goal

So lets use our algebra:

.25c = 200

if we divide 200/.25 then we will get the number of cookies with is c. Why divide you ask?

You can think about .25 dollars per cookie as a ratio. For every 1 cookie we have .25 dollars to it. Therefore .25/1 is a ratio. And we know that .25/.25 = 1 which is the exact number of cookies we want. Now we have a new ratio which is 200/ c. Again the c represents the amount of cookies since we don't know how many we have. So why not divide 200/.25 to get the number of cookies?

our answer should give us 800

.25c/.25 = 200/.25

c = 800

Answer 2

# of cookies = $200 / $0.25 = 200 * 4 = 800