(8/9) / 6 =
8/9 * 1/6 =
8/54 which reduces to 4/27 of the book each day <===
That is quite simply and astoundingly:
3.482 x 10^9
Find the difference in the y-coordinates: -3 - 1 = -4
Find the difference in the x-coordinates in the same order: 2 - 5 = -3
Divide the difference in y by the difference in x: slope = (-4)/(-3)
Reduce the fraction: slope = 4/3