It's B because all the students that attended added together is 320 and 37.5 of 320 is 120
Answer:
The original price was $312.50
Step-by-step explanation:
If the vacuum was marked down by 20%, that means it was sold for 80% of the full price. It was sold for $250, so 80% of the original price is $250.
Let's set up an equation.
80/100 of x = 250
0.8 • x = 250
Divide both sides by 0.8.
x = 312.50
The original price was $312.50
Hope this helps!
The porosity of the gravel sample is 28.75%
We have to determine.
What is the porosity of the gravel sample?
<h3>The porosity of the gravel sample;</h3>
Porosity is the term which is defined as the volume of voids present in the soil to the total volume of the soil.
The formula used to calculate the Porosity is;

A sponge is a case of a permeable fabric because it incorporates a huge number of purge spaces compared to its volume.
Porosity is the property of a question that communicates the entire volume of purge or pore space within the material.
Hence, the porosity of the gravel sample is 28.75%
Learn more about "porosity" :
brainly.com/question/2593663
What's the equation exactly?