Binary numbers: the language of computers
Answers are for parents and teachers.
1
Write the binary numbers for 1 to 8 from memory. Check with the table.
1, 10, 11, 100, 101, 110, 111, 1000.
2
Change these to decimal: 1010, 1111, 10001.
1010 = 10 (8 + 2); 1111 = 15 (8 + 4 + 2 + 1); 10001 = 17 (16 + 1).
3
Change these to binary: 12, 20, 25.
12 = 1100 (8 + 4); 20 = 10100 (16 + 4); 25 = 11001 (16 + 8 + 1).
4
Draw a 5 by 5 pixel letter T. Write its five rows in binary and in decimal.
| 31 | 1 | 1 | 1 | 1 | 1 |
| 4 | 0 | 0 | 1 | 0 | 0 |
| 4 | 0 | 0 | 1 | 0 | 0 |
| 4 | 0 | 0 | 1 | 0 | 0 |
| 4 | 0 | 0 | 1 | 0 | 0 |
Rows: 11111, 00100, 00100, 00100, 00100. In decimal: 31, 4, 4, 4, 4.
5
Show a friend how to count to 7 on your fingers using binary. Write what you did.
Answers differ. Check that three fingers are used: 1, 2 and 4, and that 7 means all three are up.