Numbers divisible by 8 must also be divisible by 1, 2, and 4.
Understanding Divisibility
Divisibility rules help us quickly determine if a number is divisible by another number without performing long division. For a number to be divisible by 8, it must also be divisible by all of 8's factors.
Factors of 8
The factors of 8 are:
- 1
- 2
- 4
- 8
Therefore, any number divisible by 8 is also divisible by 1, 2, and 4. The reference indicates, "If a number is divisible by 8, then it is also divisible by 4 also." This is correct, and we expand upon this to include all factors less than 8.
Examples
Let's look at some examples:
| Number | Divisible by 8? | Divisible by 1? | Divisible by 2? | Divisible by 4? |
|---|---|---|---|---|
| 8 | Yes | Yes | Yes | Yes |
| 16 | Yes | Yes | Yes | Yes |
| 24 | Yes | Yes | Yes | Yes |
| 32 | Yes | Yes | Yes | Yes |
| 12 | No | Yes | Yes | Yes |
| 20 | No | Yes | Yes | Yes |
As demonstrated, if a number is divisible by 8, it's also divisible by 1, 2, and 4. Numbers not divisible by 8 might still be divisible by some of these smaller factors, but not necessarily all of them.
