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2 sandwiches and 3 croissants costs £11.

3 sandwiches and 6 croissants costs £19.50.
Find the cost of a sandwich.
Find the cost of a croissant.

User JohnRC
by
5.2k points

1 Answer

10 votes

Answer:

The price of a sandwich is £2.5 and the price of a croissant is £2

Explanation:

Let s be the number of sandwiches and c be the number of croissants

Then according to given statements the equations will be:


2s+3c = 11\ \ \ \ \ \ \ Eqn\ 1\\3s+6c =19.50\ \ \ Eqn\ 2

Multiplying equation 1 by 2 and subtracting equation 2 from the new equation


2(2s+3c) = 11*2\\4s+6c = 22

Now


4s+6c-(3s+6c) = 22-19.50\\4s+6c-3s-6c = 2.5\\s = 2.5

Putting s=2.5 in equation 1


2(2.5)+3c = 11\\5+3c = 11\\3c = 11-5\\3c = 6\\(3c)/(3) = (6)/(3)\\c = 2

Hence,

The price of a sandwich is £2.5 and the price of a croissant is £2

User Gudnithor
by
5.6k points