Zoe spent
23 of her money on 12 pencils and 6 pens. The cost of each pen is 2 times the cost of each pencil. She bought some more pencils with
12 of her remaining money. How many pencils did Zoe buy altogether?
| 12 pencils + 6 pens |
Remaining
amount |
Total
amount |
| 2 p = 24 u |
1 p = 12 u |
3 p |
12
pencils |
6
pens |
More pencils |
Left |
|
| |
|
1 |
1 |
|
| 12 u |
12 u |
6 u |
|
|
Cost of 1 pencil = 1 u
Cost of 1 pen = 2 u
Cost of 12 pencils = 12 x 1 u = 12 u
Cost of 6 pens = 6 x 2 u = 12 u
Cost of 12 pencils + 6 pens
= 12 u + 12 u
= 24 u
2 p = 24 u
1 p = 24 u ÷ 2 = 12 u
Amount of remaining money that Zoe spent on buying more pencils
=
12 x 12 u
= 6 u
Number of pencils that Zoe bought with
12 of her remaining money
= 6 u ÷ 1 u
= 6
Total number of pencils that Zoe bought
= 12 + 6
= 18
Answer(s): 18
