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.
If you do try hack revise your answer works if you do .32x6 is 1.92 and add .20x10 is 200 and add 1.92 and 2.00 you get 3.92
To solve for x and y, you can use a system of equations. Let's start by setting up the equations based on the given information.
Let x be the number of 32 cents stamps and y be the number of 20 cents stamps.
Equation 1: x + y = 16 (since you bought a total of 16 stamps)
Equation 2: 32x + 20y = 392 (since you spent $3.92, which is equal to 392 cents)
To solve this system of equations, there are multiple methods you can use, such as substitution or elimination. Let's use the elimination method here.
1. Multiply both sides of Equation 1 by 20 to get rid of the y coefficient:
20x + 20y = 320
2. Subtract Equation 1 from Equation 2:
(32x + 20y) - (20x + 20y) = 392 - 320
12x = 72
3. Divide both sides of the equation by 12 to solve for x:
x = 72 / 12
x = 6
Now that we have the value of x, we can substitute it back into Equation 1 to find y.
4. Substitute x = 6 into Equation 1:
6 + y = 16
y = 16 - 6
y = 10
Therefore, you bought 6 of the 32 cents stamps and 10 of the 20 cents stamps.