Question

when determining soil texture, the percentages of the three soil particle types add up to 100%. if a soil had 40% sand and 40% silt, what would be the percentage of clay?
20%
10%
40%

Explanation:

Step1: Set up the equation

Let the percentage of clay be $x$. We know that the sum of the percentages of sand, silt and clay is 100%. So, $40 + 40+x=100$.

Step2: Solve for $x$

First, simplify the left - hand side: $80 + x=100$. Then subtract 80 from both sides: $x=100 - 80$. So, $x = 20$.

Answer:

20%