linear equation

Question

he jurassic zoo charges $14 for each adult and $7 for each child. The total bill for 169 people from a school trip was $1337. How many adults and how many children went to the zoo

Answer 1

Let x = number of children and let y = number of adults. We can set up a system of equations to model this situation:

 

x + y = 169        (169 total people went)

7x + 14y = 1337        (the total cost for children plus the total cost for adults was $1337)

 

 

Solve the first equation for y, then plug that into the second equation to solve for x:

 

y = 169 - x

 

7x + 14y = 1337

7x + 14(169 - x) = 1337

7x + 2366 - 14x = 1337

-7x + 2366 = 1337

-7x = -1029

x = 147

 

 

That means that x = 147 children went to the zoo.