At first, Archie had 121 more black beads than white beads in a box. Each day, he took out 8 black beads and 5 white beads from the box. After some time, he only had 26 white beads left in the box.
- How many beads did Archie take out from the box altogether?
- How many white beads did Archie have at first?
|
Black beads |
White beads |
Comparing black beads and white beads at first |
121 more |
|
Before |
8 u |
5 u + 26 |
Change |
- 8 u |
- 5 u |
After |
0 |
26 |
(a)
If another 121 white beads are added into the box at first, the number of black and white beads will be the same.
8 u = 5 u + 26 + 121
8 u - 5 u = 26 + 121
3 u = 147
1 u = 147 ÷ 3 = 49
Number of beads that Archie took out
= 8 u + 5 u
= 13 u
= 13 x 49
= 637
(b)
Number of beads that Archie had at first
= 637 + 26
= 663
Answer(s): (a) 637; (b) 663