Thursday
December 18, 2014

Homework Help: math

Posted by norman on Thursday, February 1, 2007 at 10:36pm.

can anyone help with this?

suppose you bought some 32 cents stamps and some 20 cents stamps. you spent $3.92 for 16 stamps. how many of each stamp did you buy?

i got the equation--.32x + .20y = $3.92 but don't know how to solve for x and y

Step 1: Solve for y in equation (1).

.20y = 3.92 - .32x


Step 2: Substitute this value for y in equation (2). This will change equation (2) to an equation with just one variable, x.


.32x + .20(3.92 - .32x)= 3.92

multiply it out

.32x + (.20 x 3.92) - (.20 x .32x) = 3.92

solve for x, then go back and plug x into the equation and solve for y


yes now i understand the process. i just couldn't get past seeing x and y. thanks

i get
.32x + .784 -.064x = 3.92
.256x + .784 = 3.92
.256x = 3.136

x=12.25?????

Hello Norman, in case u have not solved this yet, try this:

x+y = 16

32x + 20y = 392

You will get whole number answers for x and y.

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

math - suppose you bought some 32 cents stamps and some 20 cents stamps. you ...
math - still can't solve .32x + .20y = 3.92 it's my last math question for the ...
maths. - Alice spent some money on 60 stamps of two different values. The values...
intermediate algebra - A business executive bought 40 stamps for $13.68. The ...
math - suppose you bought some 32 cent stamps and some 20 cent stamps. you spent...
Algebra - Word Problems (Addition/Elimination Method). Check if my answers are ...
Math (hard) - Postcard stamps are 20 cents each, while letter stamps are 33 ...
Algebra - a colection of stamps consist of 2 cent stamps, 8 cent stamps, and 14 ...
Math - John bought some stamps. He used 3/5 of then to mail letters. He had 12 ...
algebra - An executive bought 300 stamps for $73.80. The purchase included 15 ...

Search
Members