Wendy spent
23 of her money on 12 pens and 6 pencils. The cost of each pencil is 3 times the cost of each pen. She bought some more pens with
45 of her remaining money. How many pens did Wendy buy altogether?
| 12 pens + 6 pencils |
Remaining
amount |
Total
amount |
| 2 p = 30 u |
1 p = 15 u |
3 p |
12
pens |
6
pencils |
More pens |
Left |
|
| |
|
4 |
1 |
|
| 12 u |
18 u |
12 u |
|
|
Cost of 1 pen = 1 u
Cost of 1 pencil = 3 u
Cost of 12 pens = 12 x 1 u = 12 u
Cost of 6 pencils = 6 x 3 u = 18 u
Cost of 12 pens + 6 pencils
= 12 u + 18 u
= 30 u
2 p = 30 u
1 p = 30 u ÷ 2 = 15 u
Amount of remaining money that Wendy spent on buying more pens
=
45 x 15 u
= 12 u
Number of pens that Wendy bought with
45 of her remaining money
= 12 u ÷ 1 u
= 12
Total number of pens that Wendy bought
= 12 + 12
= 24
Answer(s): 24
