Answer:
10
Step-by-step explanation:
To solve this problem you need to create a system of equations. In these equations, use a = 2-seated car and b = 4- seated car
The first equation that you can make can be a + b = 25 because the number of 2-seated cars plus the number of 4-seated cars is going to equal a total of 25 cars.
The next equation you can make is 2a + 4b = 70 because the number of seats provided by the 2-seated cars plus the number of seats provided by the 4-seated cars will equal 70 total seats.
Next, line up the equations and solve:
Step one: Line up the equations
a + b = 25
2a + 4b = 70
Step two: Multiply the top equation by -2 so that you can add both of the equations together
-2(a) + -2(b) = 25(-2) ⇒ -2a - 2b = -50
2a + 4b = 70 ⇒ 2a + 4b = 70
Step three: Add the equations
-2a - 2b = -50
+ 2a + 4b = 70
______________
2b = 20
Step four: Divide both sides by 2 in order to solve for b
2b = 20 ⇒ b = 10
Because b represents the number of 4-seated cars, you now know that there are 10 4-seated cars on the ride.
