SEARCH HOME
 Math Central Quandaries & Queries
 Question from Gregory: i have a road that is 8 miles long 20 feet wide and 4 inches deep what is the tonnage for gravel i would need

Hi Gregory,

My solution is a 3 step process.

Step 1:

First determine the density of the type of gravel you are using. There is a table of the densities of some dry materials on the SIMetric site in the UK. Look down the list to find gravel and choose the type that best fits what you are using. Record the density from the table which is in kilograms per cubic meter.

Step 2:

Go to our volume calculator, use that fact that 8 miles is 8 × 5480 = 42240 feet and calculate the volume of material you need in cubic meters. Multiply this value by the density you chose in step 1 and the result is the weight of the gravel in kilograms.

Step 3:

Google can now perform the final calculation for you. Type x kilograms in tons into Google, where x is the weight in kilograms you determined in step 2 and Google will respond with the weight in tons.

Write back if you need more assistance,
Penny

Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.