Adam has 30 green beads and 180 blue beads.
After buying the same number of beads,
the ratio of the green beads and the blue beads becomes 2 : 5.
How many beads does he buy?
|
Green |
Blue |
Difference |
Before |
30 |
180 |
150 |
Change |
+ ? |
+ ? |
|
After |
2 u |
5 u |
3 u |
At first
Difference in the number of beads
= 180 - 30
= 150
In the end
Number of green beads = 2 u
Number of blue beads = 5 u
Difference in the number of beads in units
= 5 u - 2 u
= 3 u
The difference in the number of beads between the green beads and the blue beads remains unchanged.
3 u = 150
1 u = 150 ÷ 3 = 50
Number of green beads that Adam buys
= 2 u - 30
= 2 x 50 - 30
= 100 - 30
= 70
Total number of beads that Adam buys
= 2 x 70
= 140
Answer(s): 140