2.4 Divisibility by 5

Rule: Last digit is 0 or 5. Reasoning: Same logic as rule for 2 — 10 is divisible by 5, so only the units digit matters.

Example: 45,230 → last digit 0 → divisible by 5. 45,233 → last digit 3 → not divisible.

Example 2 (edge case — divisible by 5 but NOT by 10): Is 71,825 divisible by 5? Is it divisible by 10? Last digit = 5. Since 5 satisfies “0 or 5,” 71,825 is divisible by 5. But divisibility by 10 requires the last digit to be exactly 0, and here it is 5, so 71,825 is NOT divisible by 10 (71825÷5=14365 exact, but 71825÷10=7182.5, not exact). This distinction — divisible by 5 without being divisible by 10 — trips up aspirants who conflate the two rules.

Example 3: Is 12,340 divisible by 5 and by 10 both? Last digit = 0, which satisfies both rules simultaneously → Yes to both (12340÷5=2468, 12340÷10=1234, both exact).