Calculate the percent change in each problem below.  

1. Robert wanted to buy a computer game that cost $\$25$ last week. This week when he went back to buy the game, the price was $\$35$. What was the percent of increase in the price?

   Hint (a):

   Find the increase in the price and find its percentage of the original price.

   More Help (a):

   Increase: $\$35-\$25=\$10$

   $\$10=(x)(\$25)$

2. Susan bought a jacket on sale. The original price of $\$35$ was marked down to $\$25$. What was the percent discount because of the sale?

   Hint (b):

   Follow the same strategy to find the percent discount. Remember, the percent discount is with respect to the original price.

   Answer (b):

   $28.6\%$

3. Why were your answers to parts (a) and (b) different?

   Hint (c):

   The percent increase is the amount the price increased as a percentage of the original cost.

   Answer (c):

   Each percentage is based on different original prices.