five more yellow ribbons than red ribbons. If twice the yellow ribbons is at most four times the red ribbons, at least how many red ribbons does she have

Question

five more yellow ribbons than red ribbons

twice the yellow ribbons is at most four times the red ribbons

Answer 1

Let y = number of yellow ribbons

Let r = number of red ribbons

 

y = r + 5

2y ≤ 4r

 

Substitute first equation into the second

 

2(r+5)  ≤ 4r   divide both sides by 2

r + 5  ≤ 2r     subtract r from both sides

5 ≤ r

 

r ≥ 5

There are at least 5 red ribbons