Roller coaster

Question

The roller coaster carries 92 men altogether. Some of its cars carry 4 men, and the rest carry 6 men. There are three less 6-man cars than 4-man cars. How many 4-man cars are there?

Answer 1

Let x = number of 4-man cars

 

Then, x-3 = number of 6-man cars

 

4x + 6(x-3) = 92

 

4x + 6x - 18 = 92

 

10x = 110

 

x = 11

 

Number of 4-man cars = x = 11

Number of 6-man cars = x-3 = 8