That doesn't factor neatly. Applying the quadratic formula, we find two real solutions: 3 plus or minus -1.75 times the square root of 3
t = -0.0310889132455352
t = 6.0310889132455352
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The tire size that is required for the 2006 Ford Mustang is P215/65R16 96T. This means your tire size is 16 inches and the width size is 215 millimeters. The speed rating is 118 mph and the load index 96, meaning the tires are capable of carrying a load of 1,562 pounds.
The bounds of integration are 10 and 20. The function that we are integrating is Q(t)=4(.96t)=3.84t. So the average value of Q(t) from 10 to 20 is equal to [1/(20-10)]*the integral from 10 to 20 of 3.84t dt. Simplifying, we get .384*the integral from 10 to 20 of t dt. Integrating, we get that the average value = .384(20^2 - 10^2)/2 = .196*(400 - 100) = .196 * 300 = 58.8. The average value in question is exactly 58.8 grams.