Mixture word problem with sand and soil

2 m³ of soil containing 35% sand was mixed into 6 m³ of soil containing 15% sand. What is the sand content of the mixture?


Let x% be the amount of sand in the mixture


2 × 35% + 6 × 15% = (2 + 6) × x%


2 × 0.35 + 6 × 0.15 = 8 × x/100


0.7 + 0.9 = 8x / 100


1.6 = (8/100)x


1.6 = 0.08x


1.6/0.08 = x


x = 20


Therefore, there are 20% of soil in the mixture.