A set of barstools were priced $284.80 after a 20% discount was applied. What was the price of the set of barstools before the discount?

  $356.00

Step-by-step explanation:

If d represents the discounted price, and p is the original price, you have ...

  d = p - 20% × p = p(1 -20%) = 0.80p

Then the original price is ...

  p = d/0.80 . . . . . divide by the coefficient of p

  p = $284.80/0.80 = $356.00

The price before the discount was $356.00.

The differential equation is  

Step-by-step explanation:

From the question we are told that

     The number of students are

      The number of student that have contracted the flu is  x(t)

The number of student that don't have the flu is mathematically represented as

The rate at which the disease spread is proportional to the number of interactions between students with the flu and students who have not yet contracted it, which can be mathematically represented as

=>