Nathan buys a combination of 45 cents stamps and 65 cents stamps at the post office. If he spends exactly $24.50 on 50 stamps, how many of each type did he buy?

2 Answers
Feb 12, 2018

The number of 45 cent stamps is 40 and the number of 65 cent stamps is 10.

Explanation:

Let the no. of 45 cent stamps brought be x and the no. of 65 cent stamps brought be y.

Equation 1 : x+y=50

Equation 2 : 45x+65y=2450

On solving the two equations, you get

x=40
y=10

Feb 12, 2018

40 45 cent stamps and 10 65 cent stamps

Explanation:

let x be the number of 45 cent stamps

and y be the number of 65 cent stamps

x+y=50(1)

0.45x+0.65y=24.5(2)

to eliminate x multiply (1) by 0.45

(1)0.45x+0.45y=22.5(3)

subtract term by term to eliminate x

(2)(3)

(0.45x0.45x)+(0.65y0.45y)=(24.522.5)

0.2y=2y=10

substitute y=10 in (1)

(1)x+10=50x=40

As a check

(2)(0.45×40)+(0.65×10)=24.5 correct