To solve this problem, we'll use the provided information on the key to determine the number of pencils for each mass.
1. Understand the Key:
The key indicates that one circle ([tex]\(\bigcirc\)[/tex]) represents 2 pencils.
2. Determine the frequency for each mass using the key:
- The frequency for the mass of 4 grams is represented by 2 circles.
[tex]\[
\text{Frequency for 4 grams} = 2 \times 2 = 4 \text{ pencils}
\][/tex]
- The frequency for the mass of 7 grams is represented by 0 circles.
[tex]\[
\text{Frequency for 7 grams} = 0 \times 2 = 0 \text{ pencils}
\][/tex]
3. Calculate the difference:
To find how many more pencils had a mass of 4 grams than 7 grams, we subtract the frequency for the 7 grams mass from the frequency for the 4 grams mass.
[tex]\[
\text{Difference} = 4 \text{ pencils} - 0 \text{ pencils} = 4 \text{ pencils}
\][/tex]
Thus, there are 4 more pencils with a mass of 4 grams than with a mass of 7 grams.
