SOLUTION: Hello, It costs 55c for domestic mail within Australia and $2.05 to post a letter to Europe. If I spent $10.00 to post 10 letters, how many of each type did I post? Could you as

Question 827196: Hello,
It costs 55c for domestic mail within Australia and $2.05 to post a letter to Europe. If I spent $10.00 to post 10 letters, how many of each type did I post?
Could you assist by providing algebra equation?
Thank you,
Bridgit
Answer by rothauserc(4718) (Show Source): You can put this solution on YOUR website!
let x be the number of .55 cent letters and y be the number of $2.05 letters, then
x +y = 10 and
.55x +(2.05)y = 10.00
solve first equation for x and we get x = 10 -y, then substitute in second equation
.55(10-y) +(2.05)y = 10.00
5.50 -.55y +(2.05)y = 10.00
(1.5)y = 4.50
y = 3 and x = 7
we have 7 letters at .55 cents each and 3 letters at $2.05 each
let's check the answer
7(.55) + 3(2.05) = 10.00
3.85 + 6.15 = 10.00
10.00 = 10.00
our answer checks :-)

RELATED QUESTIONS
Hello, I need help on this question please : A Canada Post outlet in small Alberta... (answered by Fombitz)

Question: You ask your roommate to mail a letter for you. Suppose there is a 0.17... (answered by ewatrrr)

The last time Carolina visited the post office, she spent $4.49 to mail letters and... (answered by clearblueskai)

The last time Carolina visited the post office, she spent $4.49 to mail letters and... (answered by addingup,MaxWong)

Hello, I am having trouble understanding and solving this problem: To mail a first... (answered by solver91311)

Is it B? I want to check my answer. Topic: Financial Mathematics If a basket of... (answered by MathLover1)

Two post 8 feet apart. From top of one post to bottom of second post at a 35 degree angle (answered by algebrapro18)

The Internet Book Company charges $6 postage for 2 books, and $10 postage for 5 books. (answered by John10)