A book shop sold
19 of the books in the morning.
15 of the remaining books are sold in the afternoon. The shop owner brought in another 140 books and there were 10 more books than there were at first. How many books were there in the shop at first?
Morning books sold |
Remaining books |
Brought-in books |
Total books |
1x5 = 5 u |
8x5 = 40 u |
|
9x5 = 45 u |
|
Afternoon books sold
|
Left books
|
|
|
|
1x8 |
4x8 |
|
|
5 u |
8 u |
32 u |
140 |
45 u + 140 |
The remaining number of books is repeated. Make the number of remaining books the same. LCM of 8 and 5 is 40.
Total number of books at first = 45 u
Total number of books in the end = 32 u + 140
Number of books left was 10 more than the number of books at first.
45 u + 10 = 32 u + 140
45 u - 32 u = 140 - 10
13 u = 130
1 u = 130 ÷ 13 = 10
Number of books at first
= 45 u
= 45 x 10
= 450
Answer(s): 450