PSLE
George had 6 jars of beads. At first, each of the jars contained the same number of beads. He took 18 beads from each jar. After that, the total number of beads left in the 6 jars was equal to the total number of beads in 4 of the jars at first. What was the number of beads in each jar at first?

	4 jars at first	Total jars in the end
Number	4	6
Value	1 u + 18	1 u
Total value	4 u + 72	6 u

Number of beads in each jar in the end = 1 u
Number of beads in each jar at first = 1 u + 18

Number of beads in 4 jars at first 
= 4 x (1 u + 18)
= 4 u + 72

Total number of beads left in the 6 jars was equal to total number of beads in 4 jars at first.

6 u = 4 u + 72 
6 u - 4 u = 72
2 u = 72

1 u = 72 ÷ 2 = 36

Number of beads in each jar at first
= 1 u + 18
= 36 + 18
= 54

Answer(s): 54