The scoop of an excavator holds 27 ft3 of sand. if the capacity of a freight car is 40 tons of sand and we know that 1 ft3 of sand weighs 0.5 tons, how many freight cars can be filled with 120 loads?

27ft³=x tons
1ft³=0.5 tons



Cross multiply
1x=13.5tons
x=13.5tons

So one scoop/load carries 13.5 tons of sand. Lets see how many 120 loads can carry.

13.5tons*120loads=1620 tons of sand

Now lets see how freight cars it would take to hold 1620 tons of sand

1620/40=40.5 freight cars

Since you can't have .5 of a freight car, lets round 40.5 up to 41

Answer=41 freight cars

Step 1: 6x-10=1; step 2: 6x=11