What is the price per egg and price per pancake?

Question

Isaiah and Tali went to a diner for breakfast. Isaish ordered 3 eggs and 4 pancakes, and paid $7.20. Tali ordered 2 eggs and 2 pancakes, and paid $4.00. The diner does not charge sales tax.

What is the price per egg and price per pancake?

Answer 1

Easy way to figure this out ...

x = eggs
y = pancakes

3x + 4y = 7.20
2x + 2y = 4.00

so x + y = $2.00

the Isaish order 3x + 4y = (3x + 3y) + y
we already know x + y = 2 so 3x + 3y = 6
6 + y = 7.20
y = 1.20
x = 0.80

Answer 2

this may seem confusing, but i'll try to make it simple:
first, write the equations from the given info.
3e+4p=7.20
2e+2p=4.00
multiply the second one by 2, then you get
4e+4p=8.00
subtract the first equation from that
4e+4p=8.00
- 3e+4p=7.20
____________
e=.80 The price for the eggs is $.80
now plug .80 in for e in one of the equations
2e+2p=4.00
2(.80)+2p=4.00
1.60+2p=4.00
2p=2.40
p=1.20
the price of the pancakes is $1.20

Answer 3

x = eggs
y = pancakes

3x + 4y = $7.20
2x + 2y = $4.00

so x + y = $2.00

the Isaish order 3x + 4y = (3x + 3y) + y
we already know x + y = 2 so 3x + 3y = 6
6 + y = 7.20
y = $1.20
x = $0.80

Answer 4

3e + 4p = 7.20
2e + 2p = 4.00

Solving for p on the bottom equation gives you:

p = 2.00 - e

therefore, if we insert this into the top equation and solve for e we get:

3e + 4(2.00 - e) = 7.20
3e + 8.00 - 4e= 7.20

3e - 4e = 7.20 - 8.00
e= 0.80

therefore, p = 1.20

Answer 5

x = eggs
y = pancakes

3x + 4y = 7.20
2x + 2y = 4.00


3x + 4y = 7.20
-4x -4y = -8.00

-x = -.80
x = 0.80


3(0.80) + 4y = 7.20
2.40 + 4y = 7.20
4y = 4.80
y = 1.20

so,an egg costs $0.80 and a pancake costs $1.20

Answer 6

egg = $ .80
pancake = $1.20