Box U contains 14 black beads and 4 pink beads. Box V contains 84 black beads and 34 pink beads. How many pink beads and black beads must be moved from Box V to put into Box U so that 50% of the beads in Box A are black and 80% of the beads in Box V are black?

	Box U		Box V
	Black beads	Pink beads	Black beads	Pink beads
Before	14	4	84	34
Change	+ ?	+ ?	- ?	- ?
After	1 u	1 u	4 p	1 p

50% = ⁵⁰₁₀₀ = 12

80% = ⁸⁰₁₀₀ = 45

Number of black beads = 14 + 84 = 98 

Number of pink beads = 4 + 34 = 38 

1 u + 4 p = 98 --- (1)

1 u + 1 p = 38 ---(2)

(1) - (2)
(1 u + 4 p) - (1 u + 1 p) = 98 - 38
4 p - 1 p = 60
3 p = 60

1 p = 60 ÷ 3 = 20

From (2):
1 u + 1 p = 38
1 u + 1 x 20 = 38
1 u + 20 = 38

1 u = 38 - 20 = 18

Number of pink beads to be moved from Box V to Box U
= 34 - 1 p
= 34 - 1 x 20
= 34 - 20
= 14

Number of black beads to be moved from Box V to Box U
= 1 u - 14
= 18 - 14
= 4

Total number of pink and black beads to be moved from Box V to Box U
= 14 + 4
= 18

Answer(s): 18