A block of ice loses one third of its weight every hour. After 2 hours, the block weighs 40 pounds. How much did the block weigh to begin with?
let it's original weight be x lbs
after 1 hour it weighed 2/3 x lbs
after 2 hours it weighed (2/3)(2/3)x lbs
4/9 x = 40
x = 40(9/4) = 90 lbs
To solve this problem, we can set up an equation based on the given information.
Let's suppose the weight of the block of ice to begin with is "x" pounds.
We know that after 2 hours, the block weighs 40 pounds, which is two-thirds of its initial weight.
So, we can write the equation as:
x - (1/3)x = 40
Simplifying the equation, we get:
(2/3)x = 40
To solve for "x" (the initial weight of the block), we can multiply both sides of the equation by (3/2):
x = 40 * (3/2)
By performing the operations, we find:
x = 60
Therefore, the block of ice initially weighed 60 pounds.