1. **Stating the problem:**
We are given that the length of a string, $L$, is 30 cm when rounded to the nearest 10 cm.
Daniella wrote the inequality $25 \leq L < 34$ to represent the lower and upper bounds of $L$.
We need to:
a) Find an example length that shows Daniella's inequality is incorrect.
b) Find the correct inequality for $L$.
2. **Understanding rounding to the nearest 10 cm:**
When rounding to the nearest 10, numbers from halfway below to halfway above round to the same 10.
For 30 cm, the rounding range is from $25$ cm up to but not including $35$ cm.
This means any length $L$ where $25 \leq L < 35$ will round to 30 cm.
3. **Checking Daniella's inequality:**
Daniella wrote $25 \leq L < 34$.
This excludes lengths between 34 cm and 35 cm, which should also round to 30 cm.
4. **Example showing Daniella's inequality is incorrect:**
Take $L = 34.5$ cm.
Since $34.5$ rounds to $30$ when rounded to the nearest 10, but $34.5$ is not less than $34$, it does not satisfy Daniella's inequality.
5. **Correct inequality:**
The correct bounds for $L$ are:
$$25 \leq L < 35$$
This includes all lengths that round to 30 cm when rounded to the nearest 10.
**Final answers:**
a) Example length: $34.5$ cm
b) Correct inequality: $25 \leq L < 35$
String Length Bounds 1698C4
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