Linda had 350 beads. ³₇ were pink and the rest were green and silver. The ratio of the number of green beads to the number of silver beads was 1 : 4. Linda decided to buy some more pink beads to increase the number of pink beads to half of the total number of beads.

1. How many less green beads than pink beads did he have at first?
2. How many more pink beads did he have to buy?

Pink beads	Green beads	Silver beads	Total
3x5	4x5
	1x4	4x4
15 u	4 u	16 u	350

	Pink beads	Green beads	Silver beads
Before	15 u	4 u	16 u
Change	+ ?
After	20 u	20 u
Comparing pink, green and silver beads in the end	1	1

(a)
The total number of green beads and silver beads is repeated. Make the total number of green beads and silver beads the same.  LCM of 4 and 5 is 20.

Total number of beads at first
= 15 u + 4 u + 16 u
= 35 u

35 u = 350

1 u = 350 ÷ 35 = 10

Number of less green beads than pink beads at first
= 15 u - 4 u
= 11 u
= 11 x 10
= 110

(b)
Number of more pink beads that Linda had to buy
= 20 u - 15 u
= 5 u
= 5 x 10
= 50

Answer(s): (a) 110; (b) 50