Erina has a bag that starts with 50 marbles in it: 10 green marbles and 40 purple marbles. She wants to increase the ratio of green to purple marbles by adding some more marbles to the bag. Which of the following additions would increase this ratio?

I. 3 green and 1 purple

II. 1 green and 3 purple

III. 3 green and 3 purple

All can be added

Step-by-step explanation:

Initial ratio is green : purple = 10 : 40

= 1 : 4

If we add more of green marbles and purple marbles to the initial one, there will definitely be an increase in the ratio

For instance,

I. 3 green and 1 purple

II. 1 green and 3 purple

III. 3 green and 3 purple

All of them will cause and increase in the ratio.

5x+40

5(x + 8)

7x - 49

7(x - 7)

18x + 9

9(2x + 1)

15x - 10

5(3x - 2)

step-by-step explanation:

for number one all you have to do is factor 5 out of 5x + 40

for number 2 factor 7 out of 7x - 49

for number three factor 9 out of 18x + 9

for number four factor 5 out of 15x - 10