Eva spent
23 of her money on 14 notebooks and 7 pens. The cost of each pen is 2 times the cost of each notebook. She bought some more notebooks with
12 of her remaining money. How many notebooks did Eva buy altogether?
| 14 notebooks + 7 pens |
Remaining
amount |
Total
amount |
| 2 p = 28 u |
1 p = 14 u |
3 p |
14
notebooks |
7
pens |
More notebooks |
Left |
|
| |
|
1 |
1 |
|
| 14 u |
14 u |
7 u |
|
|
Cost of 1 notebook = 1 u
Cost of 1 pen = 2 u
Cost of 14 notebooks = 14 x 1 u = 14 u
Cost of 7 pens = 7 x 2 u = 14 u
Cost of 14 notebooks + 7 pens
= 14 u + 14 u
= 28 u
2 p = 28 u
1 p = 28 u ÷ 2 = 14 u
Amount of remaining money that Eva spent on buying more notebooks
=
12 x 14 u
= 7 u
Number of notebooks that Eva bought with
12 of her remaining money
= 7 u ÷ 1 u
= 7
Total number of notebooks that Eva bought
= 14 + 7
= 21
Answer(s): 21
