1. **State the problem:** We need to determine if each equation relating hours (h), days (d), months (m), and years (y) is always true, sometimes true, or false.
2. **Recall the definitions and conversions:**
- 1 day = 24 hours
- 1 year = 12 months
- Number of days in a month varies (28 to 31 days)
3. **Analyze each equation:**
**Equation 1: $d = 24h$**
- This suggests 1 day equals 24 hours.
- But $h$ represents hours, so if $h=1$, then $d=24$ days, which is incorrect.
- Actually, 1 day = 24 hours means $h = 24d$, not $d = 24h$.
- Therefore, this equation is **false**.
**Equation 2: $m = 12y$**
- This suggests months equal 12 times years.
- Since 1 year = 12 months, $m = 12y$ is **always true**.
**Equation 3: $d = 31m$**
- This suggests days equal 31 times months.
- Months have varying days: 28, 29, 30, or 31.
- So, $d = 31m$ is **sometimes true** (only for months with 31 days).
4. **Summary:**
- $d = 24h$ is false.
- $m = 12y$ is always true.
- $d = 31m$ is sometimes true.
5. **Final answers:**
- $d = 24h$: False
- $m = 12y$: Always true
- $d = 31m$: Sometimes true
Time Equations
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