To determine how much manure is required per hectare to supply 1.5 kg of phosphorus, we need to follow a systematic approach. Let's break it down step-by-step.
Step 1: Understand the Problem
We know that:
- The crop requires
1.5 kg of phosphorus per hectare.
- Each
1 kg of manure contains
0.49 kg of phosphorus.
Step 2: Set Up the Calculation
To find out how many kilograms of manure are needed to provide the required phosphorus, we can use the following formula:
[
\text{Amount of manure required (kg)} = \frac{\text{Required phosphorus (kg)}}{\text{Phosphorus content in manure (kg/kg)}}
]
Step 3: Plug in the Values
Now, we can substitute the values into the formula:
[
\text{Amount of manure required (kg)} = \frac{1.5 \text{ kg}}{0.49 \text{ kg/kg}}
]
Step 4: Perform the Calculation
Now, we perform the division:
[
\text{Amount of manure required (kg)} = \frac{1.5}{0.49} \approx 3.06 \text{ kg}
]
Step 5: Analyze the Options
Now, let's compare our calculated value with the provided options:
- A. 2.47
- B. 2.97
- C. 7.35
- D. 12.39
None of the options match our calculated value of approximately 3.06 kg. However, it seems there might have been a misunderstanding in the options provided or the calculation itself.
Step 6: Re-evaluate the Calculation
Let’s double-check the calculation to ensure accuracy:
- Calculate the amount of manure needed:
[
\text{Amount of manure required (kg)} = \frac{1.5}{0.49} \approx 3.06 \text{ kg}
]
This confirms our previous calculation.
Step 7: Evaluate the Options
Since none of the options match our calculated value, we can analyze why the other options might be incorrect or weaker:
- Option A (2.47 kg): This is less than the required phosphorus amount, which means it would not provide enough phosphorus for the crop.
- Option B (2.97 kg): This is also less than the required phosphorus amount, thus insufficient.
- Option C (7.35 kg): This is more than double the required amount, which is excessive and not necessary.
- Option D (12.39 kg): This is significantly higher than needed, leading to waste and potential environmental issues.
Conclusion
The correct calculation shows that approximately
3.06 kg of manure is needed to meet the phosphorus requirement of 1.5 kg per hectare. Since none of the options provided match this calculation, it suggests a possible error in the options given.
Revision Summary
- To find the amount of manure needed, divide the required phosphorus by the phosphorus content in manure.
- The calculation shows that approximately 3.06 kg of manure is needed.
- None of the provided options (A, B, C, D) are correct based on the calculation.
- Always double-check calculations and ensure options align with the results obtained.