47. The school has bought a batch of science fiction novels and distributed them to 10 groups. After each group received 5 books, there were not enough books left to distribute. What is the minimum number of science fiction novels in this batch?
A number or a short expression. Spacing, $ signs and \frac vs / are all fine.
Official solution
Answer: 51
Source: NuminaMath-1.5,
licensed Apache-2.0.
Statement and solution reproduced as published; topic, difficulty and ordering added
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