Adam has 210 red beads.
He has 5 times as many red beads as blue beads.
After he buys an equal number of red and blue beads,
the number of red beads is 4 times that of the blue beads.
- How many red beads are there in the end?
- How many blue beads are there in the end?
- How many beads are there in the end?
- How many beads does Adam buy?
|
Red beads |
Blue beads |
Difference |
Before |
5 x 3 = 15 u |
1 x 3 = 3 u |
4 x 3 = 12 u |
Change |
+ ? |
+ ? |
|
After |
4 x 4 = 16 u |
1 x 4 = 4 u |
3 x 4 = 12 u |
(a)
The difference in the number between the red and blue beads at first and in the end remains unchanged.
LCM of 4 and 3 is 12.
15 u = 210
1 u = 210 ÷ 15 = 14
Number of red beads in the end
= 16 u
= 16 x 14
= 224
(b)
Number of blue beads in the end
= 4 u
= 4 x 14
= 56
(c)
Total number of beads in the end
= 224 + 56
= 280
(d)
Total number of beads that Adam buys
= (16 u - 15 u) x 2
= 1 u x 2
= 2 u
= 2 x 14
= 28
Answer(s): (a) 224; (b) 56; (c) 280; (d) 28