Some identical workbooks can be arranged in exactly 13 per row. If the same number of workbooks is arranged in rows of 8 workbooks each, there will be 4 more rows and 3 workbooks left over. How many workbooks are there altogether?
| |
13 per row |
8 per row |
| Number |
1 u |
1 u + 4 |
| Value |
13 |
8 |
| Total value |
13 u |
8 u + 32 + 3 |
Number of rows if the workbooks are arranged in rows of 13 = 1 u
Number of rows if the workbooks are arranged in rows of 8 = 1 u + 4
Total number of workbooks if they are arranged in rows of 13
= 13 x 1 u
= 13 u
Total number of workbooks if they are arranged in rows of 8
= 8 x (1 u + 4) + 3
= 8 u + 32 + 3
= 8 u + 35
The total number of workbooks remains the same for both cases.
13 u = 8 u + 35
13 u - 8 u = 35
5 u = 35
1 u = 35 ÷ 5 = 7
Total number of workbooks
= 13 u
= 13 x 7
= 91
Answer(s): 91
