Question

Liam's breakfast was an egg and cheese biscuit with a carton of milk. He spent a total of $5.65. Finn spent $7.65 on an egg and cheese biscuit and two cartons of milk. How much was an egg and cheese biscuit?

Answer 1

Answer:

An egg and cheese biscuit was $3.65.

Step-by-step explanation:

Liam's breakfast was:

$P = E + C + M$

Where:

P: total price

E: egg

C: cheese biscuit

M: carton of milk  

$P = E + C + M$

$5.65 = E + C + M$   (1)

Now, Finn's breakfast was:

$P = E + C + 2*M$

$7.65 = E + C + 2*M$   (2)      

By subtracting equation (2) from (1) we have:

$7.65 - 5.65 = 2M - M$

$M = 2$

Hence, the price of a carton of milk is $2, so by entering this value into equation (1) we can find the price of an egg and cheese biscuit:

$5.65 = E + C + M$

$5.65 - 2 = E + C$

$E + C = 3.65$

Therefore, an egg and cheese biscuit was $3.65.

I hope it helps you!