Gabby spent
23 of her money on 10 pens and 8 pencils. The cost of each pencil is 4 times the cost of each pen. She bought some more pens with
23 of her remaining money. How many pens did Gabby buy altogether?
| 10 pens + 8 pencils |
Remaining
amount |
Total
amount |
| 2 p = 42 u |
1 p = 21 u |
3 p |
10
pens |
8
pencils |
More pens |
Left |
|
| |
|
2 |
1 |
|
| 10 u |
32 u |
14 u |
|
|
Cost of 1 pen = 1 u
Cost of 1 pencil = 4 u
Cost of 10 pens = 10 x 1 u = 10 u
Cost of 8 pencils = 8 x 4 u = 32 u
Cost of 10 pens + 8 pencils
= 10 u + 32 u
= 42 u
2 p = 42 u
1 p = 42 u ÷ 2 = 21 u
Amount of remaining money that Gabby spent on buying more pens
=
23 x 21 u
= 14 u
Number of pens that Gabby bought with
23 of her remaining money
= 14 u ÷ 1 u
= 14
Total number of pens that Gabby bought
= 10 + 14
= 24
Answer(s): 24
