How many of each color are there?

Question

A bowl contains 300 skittles that are red and green. There are 3 times as many green skittles as there are red skittles. Write a system of equations problem to find the number of red skittles and green skittles.

Answer 1

r + g = 300

g = 3r

 

Now, we can substitute two ways...

 

r + 3r = 300

4r = 300

r = 75

g = 3(75) = 225

 

Ooooorrr, solve the first equation for g and set the two "values" for g equal to each other...

 

g = 300 - r

300 - r = 3r

300 = 4r

75 = r

s = 300 - 75 = 225

 

Hope this helps!