In January 2013 a country‘s first class mail rates increased to 42 cents for the 1st ounce and 22 cents for each additional ounce. Is Sabrina spent $16.24 for a total of 52 stamps of these two denominations how many stamps of each denomination did she buy?

She bought ___ 42 cent stamps
And _____ 22 cent stamps

Respuesta :

Answer:

  • She bought 24 42-cent stamps
  • And 28 22-cent stamps

Step-by-step explanation:

Let n represent the number of 42-cent stamps Sabrina bought. Then 52-n is the number of 22-cent stamps she bought. Her total expense was ...

  0.42n +0.22(52 -n) = 16.24 . . . . total price of stamps

  0.20n + 11.44 = 16.24 . . . . . . . . . simplify

  0.20n = 4.80 . . . . . . . . . . . . . . . . subtract 11.44

  n = 24 . . . . . . . . . . . . . . . . . . . . . . divide by the coefficient of n

  52-n = 28 . . . . . . . . . . . . . . . . . . . find the number of 22-cent stamps

She bought 24 42-cent stamps and 28 22-cent stamps.

She bought 24-42 cent stamps

And, 28-22 cent stamps.

Calculation of number of stamps:

Here we assume  n be the number of 42-cent stamps

The equation should be

0.42n +0.22(52 -n) = 16.24

0.20n + 11.44 = 16.24

0.20n = 4.80

n = 24

Now

= 52 - n

= 52 - 24

= 28

Learn more about the cent here; https://brainly.com/question/3789339