Question

This passage describes leaf type in barnyard grass plants.

a barnyard grass seedling with drooping leaves
Barnyard grass is a weed that often grows in rice fields. A barnyard grass seedling can have upright leaves that stick straight up or drooping leaves that curl down.
Rice seedlings also have upright leaves. So, farmers weeding their rice fields by hand are more likely to mistake barnyard grass seedlings with upright leaves for rice plants. Farmers are more likely to recognize and remove barnyard grass seedlings with drooping leaves.
The table below describes a possible population of barnyard grass plants at the start of a period of time and at the end of that period. The table shows leaf type in the population at each point in time.
Complete the table. Write the exact answers as whole numbers or decimals.
Data about a population of barnyard grass plants
Point in time Number with upright leaves Number with drooping leaves Percentage with upright leaves Percentage with drooping leaves
Start 358 142
%
%
End 156 644
%
%

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Answer 1

To complete the table, let's calculate the percentages based on the numbers given for both the start and the end of the period.

### At the Start

1. **Total Number of Plants at the Start**:
- Upright Leaves: 358
- Drooping Leaves: 142
- Total = 358 + 142 = 500

2. **Percentage with Upright Leaves**:
\[
\text{Percentage with Upright Leaves} = \left( \frac{358}{500} \right) \times 100 = 71.6\%
\]

3. **Percentage with Drooping Leaves**:
\[
\text{Percentage with Drooping Leaves} = \left( \frac{142}{500} \right) \times 100 = 28.4\%
\]

### At the End

1. **Total Number of Plants at the End**:
- Upright Leaves: 156
- Drooping Leaves: 644
- Total = 156 + 644 = 800

2. **Percentage with Upright Leaves**:
\[
\text{Percentage with Upright Leaves} = \left( \frac{156}{800} \right) \times 100 = 19.5\%
\]

3. **Percentage with Drooping Leaves**:
\[
\text{Percentage with Drooping Leaves} = \left( \frac{644}{800} \right) \times 100 = 80.5\%
\]

### Completed Table

| Point in Time | Number with Upright Leaves | Number with Drooping Leaves | Percentage with Upright Leaves | Percentage with Drooping Leaves |
|---------------|-----------------------------|-----------------------------|-------------------------------|-------------------------------|
| Start | 358 | 142 | 71.6% | 28.4% |
| End | 156 | 644 | 19.5% | 80.5% |

In summary, the whole numbers or decimals for the percentages are:

- Start: **71.6%** with upright leaves, **28.4%** with drooping leaves.
- End: **19.5%** with upright leaves, **80.5%** with drooping leaves.