There are 20% as many pink marbles as green marbles in Jaslyn's collection of marbles. The number of black marbles is 30% fewer than the number of green marbles. There are 550 more black marbles than pink marbles.

1. Find the total number of marbles in the collection.
2. What percentage are the number of green marbles as compared to the number of black marbles? Leave your answer as a mixed number in its simplest form.

Pink	Green	Black
1x2	5x2
	10x1	7x1
2 u	10 u	7 u

(a)
20% = ²⁰₁₀₀ = ¹₅

100% - 30% = 70%
70% = ⁷⁰₁₀₀ = ⁷₁₀

The number of green marbles is the repeated identity. Make the number of green marbles the same.  LCM of 5 and 10 is 10.

Number of more black marbles than pink marbles
= 7 u - 2 u
= 5 u

5 u = 550

1 u = 550 ÷ 5 = 110

Total number of marbles in the collection
= 2 u + 10 u + 7 u 
= 19 u
= 19 x 110
= 2090

(b)
Percentage of the number of green marbles as compared to the number of black marbles
= ¹⁰₇ x 100%
= ¹⁰⁰⁰₇ %
= 142⁶₇ %

Answer(s): (a) 2090; (b) 142⁶₇ %