Mini Cross-Number
Which digit replaces x in this crossnumber?
Age
11 to 14
Challenge level
Problem
What is the digit x in this cross-number?
Across Down
1. A cube 1. One less than a cube
3. A cube 2. A number
If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.
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If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.
Student Solutions
Answer: 4
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1$^3$=1, 2$^3$=8, 3$^3$=27, 4$^3$=64, 5$^3$ is more than 100
1 across is 27 or 64
| 1 across | 1 down | 3 across |
|---|---|---|
| 27 | 26 | 64 |
| 64 | 63 | no cube begins with 3 |
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