how many children and how many adults attended

Question

The admission fee at a small fair is 2.00 for children and 3.50 for adults.on a certain day 775 people enter the fair and 2225 is collected.how many children and how many adults attended 

 

Answer 1

a + c = 775

3.5a + 2c = 2225

 

c = 775 - a

 

3.5a + 2(775 - a) = 2225

3.5a + 1550 - 2a = 2225

1.5a = 675

a = 450

 

c = 775 - 450 = 325

 

Boom.