Jack can read 45 pages of his book in one and a half hours. At that rate, how long will it take him to read the entire 300-page book?

Answer 1

45/1.5 = 300/x

ratio of pages to hours is a constant

solve for x

cross multiply

45x = 1.5(300)

divide by 45

x = 1.5(300)/45

= 450/45

= 10 hours to read 300 pages at the same speed

300/45 = 6 2/3 times as long

6 2/3 times 1.5 = 20/3 times 3/2 = (20/3)(3/2) = 10 hours