Esther spent
45 of her money on 11 notebooks and 7 markers. The cost of each marker is 3 times the cost of each notebook. She bought some more notebooks with
78 of her remaining money. How many notebooks did Esther buy altogether?
11 notebooks + 7 markers |
Remaining amount |
Total amount |
4 p = 32 u |
1 p = 8 u |
5 p |
11 notebooks |
7 markers |
More notebooks |
Left |
|
|
|
7 |
1 |
|
11 u |
21 u |
7 u |
|
|
Cost of 1 notebook = 1 u
Cost of 1 marker = 3 u
Cost of 11 notebooks = 11 x 1 u = 11 u
Cost of 7 markers = 7 x 3 u = 21 u
Cost of 11 notebooks + 7 markers
= 11 u + 21 u
= 32 u
4 p = 32 u
1 p = 32 u ÷ 4 = 8 u
Amount of remaining money that Esther spent on buying more notebooks
=
78 x 8 u
= 7 u
Number of notebooks that Esther bought with
78 of her remaining money
= 7 u ÷ 1 u
= 7
Total number of notebooks that Esther bought
= 11 + 7
= 18
Answer(s): 18