Calculus problem: A drug manufacturer has developed a time-release capsule with the number of milligrams of the drug in the bloodstream given by

S = 40[tex]x^{\frac{19}{7} }[/tex] − 560[tex]x^{\frac{12}{7} }[/tex] + 1960[tex]x^{\frac{5}{7} }[/tex]

where x is in hours and 0 ≤ x ≤ 7. Find the average number of milligrams of the drug in the bloodstream for the first 7 hours after a capsule is taken. (Round your answer to the nearest whole number.)

Solution: _____ mg