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

Answer:

20 roses cost $91.65

Step-by-step 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:

$c = kx$

$54.99 = k * 12$

$54.99 = 12k$

$k = \frac{54.99}{12}$

$k = 4.5825$

For 20 roses

$c = kx$

Where

$k = 4.5825$

$x = 20$

$c = 4.5825 * 20$

$c = 91.65$