Adam has 20 red beads and 200 green beads.
After buying the same number of beads,
the ratio of the red beads and the green beads becomes 3 : 8.
How many beads does he buy?
|
Red |
Green |
Difference |
Before |
20 |
200 |
180 |
Change |
+ ? |
+ ? |
|
After |
3 u |
8 u |
5 u |
At first
Difference in the number of beads
= 200 - 20
= 180
In the end
Number of red beads = 3 u
Number of green 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 red beads and the green beads remains unchanged.
5 u = 180
1 u = 180 ÷ 5 = 36
Number of red beads that Adam buys
= 3 u - 20
= 3 x 36 - 20
= 108 - 20
= 88
Total number of beads that Adam buys
= 2 x 88
= 176
Answer(s): 176