Adam has 50 green beads and 150 red beads.
After buying the same number of beads,
the ratio of the green beads and the red beads becomes 3 : 8.
How many beads does he buy?
|
Green |
Red |
Difference |
Before |
50 |
150 |
100 |
Change |
+ ? |
+ ? |
|
After |
3 u |
8 u |
5 u |
At first
Difference in the number of beads
= 150 - 50
= 100
In the end
Number of green beads = 3 u
Number of red beads = 8 u
Difference in the number of beads in units
= 8 u - 3 u
= 5 u
The difference in the number of beads between the green beads and the red beads remains unchanged.
5 u = 100
1 u = 100 ÷ 5 = 20
Number of green beads that Adam buys
= 3 u - 50
= 3 x 20 - 50
= 60 - 50
= 10
Total number of beads that Adam buys
= 2 x 10
= 20
Answer(s): 20