Question

A florist sells a dozen long-stemmed red roses for $54.99. In honor of their 16th wedding anniversary, a man wants to buy 20 roses for his wife. (Hint: How many roses are in one dozen?)

Let c represent the cost of 20 roses. Write a proportion, in terms of c, that can be used to solve for the cost of 20 roses.


What will the roses cost (in dollars)?

Answer 1

20 roses cost $91.65

Explanation:

Given

1 dozen rose = $54.99

Required

Determine the cost of 20 roses

To calculate the proportion, we make use of:

`c = kx`

Where

c = cost

k = constant of proportionality

x = number of roses

For a dozen rose

`c = 54.99` and
`x = 12`

So:

`c = kx`

`54.99 = k * 12`

`54.99 = 12k`

`k = (54.99)/(12)`

`k = 4.5825`

For 20 roses

`c = kx`

Where

`k = 4.5825`

`x = 20`

`c = 4.5825 * 20`

`c = 91.65`