Question

plant scientists recommend that the best soil for growing vegetables contain a mix of 40% sand, 20% clay, and 40% silt. a plant scientist collects a sample of soil in a jar. she uses water to separate the soil into layers and measures the height, in centimeters, of each layer in the jar. the table shows the results.
based on the results, which conclusion can the plant scientist make about this sample of soil with regard to growing vegetables?
the soil has too much sand.
the soil has just enough sand.
the soil has too much clay and silt.
the soil has just enough clay and silt.

Explanation:

Step1: Calculate the total height of the soil sample

The total height of the soil sample is the sum of the heights of the sand, clay, and silt layers.
$$30 + 10+20=60$$ (cm)

Step2: Calculate the percentage of sand in the sample

The percentage of sand is calculated as $\frac{\text{height of sand layer}}{\text{total height of sample}}\times100\%$.
$$\frac{30}{60}\times100\% = 50\%$$

Step3: Compare with the recommended percentage

The recommended percentage of sand for growing vegetables is $40\%$. Since $50\%>40\%$, the soil has too much sand.

Answer:

The soil has too much sand.