Jhonny uses a wheelbarrow to move planting soil to a delivery truck. The volume of the planting soil that fits in the wheelbarrow measures 2 feet by 3 feet by 1.5 feet.The delivery truck measures 11 feet by 8 feet and is 6 feet tall. Jhonny puts planting soil in the delivery truck until the truck is 70% full. What is the minimum number of times Jhonny needs to use the wheelbarrow until the delivery truck is 70& full?

Total volume of the delivery truck with dimensions 11 × 8 × 6 is given y multiplying the the dimensions. Thus the volume of the delivery truck is 528 [tex]feet ^{3}[/tex].

Total volume of the wheelbarrow with dimensions 2 × 3 × 1.5 is given y multiplying the the dimensions. Thus the volume of the wheelbarrow truck is 9 [tex]feet ^{3}[/tex].

Now the delivery truck is 70% full. Therefore only 30% of the truck is left to be loaded. Thus 30% of the total volume of the truck is given by 30% of 528[tex]feet ^{3}[/tex].

∴ Leftover space in the truck is = [tex]\frac{30}{100}[/tex] × 528 = 158.4 [tex]feet ^{3}[/tex].

Total number of time the wheelbarrow is used and the planting soil is put in the truck is given by taking the ratio of the leftover space to the volume of the wheelbarrow.

Thus the minimum number of times is = [tex]\frac{158.4}{9}[/tex] = 17.6 ≅ 18. (rounded off to the nearest highest integer).