Question

2m3 of soil containing 28% silt was mixed into 1 m3 of soil containing 13% of silt. What is the silt content mixture?

Answer 1

alright
so
28% of 2 m³=0.28 times 2=0.56 m³ of silt in the first mixture

13% of the 1 m³=0.13 times 1=0.13 m³ of silt in 2nd

total is 0.56 m³+0.13 m³=0.69 m³ of silt
and the total is 2m³+1m³=3m³

so
0.69/3=0.23=23%

answer is D