What is the weight of a 500 kg boulder on the moon?

F = 810 [N]

Explanation:

To solve this problem we must use the acceleration of gravity of the moon, which according to information provided by the internet we can see that the gravitational acceleration corresponds to 1.62 [m/s^2].

The weight of a body corresponds to the product of mass by gravity, so with the following equation we can find the weight.

F =m*g

F = 500 * 1.62

F = 810 [N]

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form