Chapter 7.5, Problem 13P

* Suppose that there are 400 pounds of freshly picked tomatoes and that 99% of their weight is water. After one day, the same tomatoes only weigh 200 pounds due to evaporation of water. (The tomatoes consist of water and solids. Only the water evaporates; the solids remain.)

a. How many pounds of solids are present in the tomatoes? (Notice that this is the same when they are freshly picked as after one day.)

b. Therefore, when the tomatoes weigh 200 pounds, what percent of the tomatoes is water?

c. Is it valid to use the following proportion to solve for the percent of water, x, in the tomatoes when they weigh 200 pounds?

   $\frac{0.99}{400}=\frac{x}{200}$

If not, why not?