18 people order soup and sandwiches for lunch. Sandwiches cost 7.75 each and 4.50 the soup. Total cost of 18 luchees was 113.50 how many sandwiches were ordered

Sagot :

Let soups be represented by x and sandwiches by y.

x + y = 18
4.5x + 7.75y = 113.50

x = 18 - y

4.5(18 -y) + 7.75 y = 113.5

= 81 - 4.5y + 7.75y = 113.5

81 + 3.25y = 113.5

3.25y = 32.5

y = 10.

x + y = 18
x + 10 = 18

Thus, x = 8. 

Thus, 8 soups and 10 sandwiches were ordered.
Let the soup be x  and sandwich  be  y
7.75x+4.50y=113.50
x=18-y
7.75(18-y)+4.50y=113.50
y=10
x+y=18
so x=8