Answer and explanation:
Given:
Royal soil= $6.50 per pound
Royal peasant = $2 per pound of 10 pounds
Blend total pounds is x+10, price is unknown hence solved below
Using algebra
We find unknown x = number of pounds of royal soil
$6.50(x)+$2(10)=6.50x+20/x+10(x+10)
= 6.50x+20= 6.50x²+85x+200
B. x<3 is the answer to the question you have asked
That "ad^3" bothers me; I'm not sure what you mean here.
I'm going to assume that you have (1/4*a*d^3)^2.
If that's the case, then you have (1/4)^2 * a^2 * d^6 = (1/16)*a^2*d^6.
If this is not what you were hoping for, double check to ensure that you have copied down this problem exactly as it was presented.