Question

Jen Butler has been pricing​ Speed-Pass train fares for a group trip to New York. Three adults and four children must pay $ 99.  Two adults and three children must pay $ 70.  Find the price of the​ adult's ticket and the price of a​ child's ticket.

Answer 1

Answer:

An adult ticket is 17

A childs ticket costs 12 dollars

Step-by-step explanation:

Let a = adult price

c = child price

3a + 4c = 99

2a + 3c = 70

Multiply the first equation by 2

2(3a + 4c) = 99*2

6a + 8c = 198

Multiply the second equation by -3

-3 (2a + 3c) = 70*-3

-6a -9c = -210

Add these new equations together

6a + 8c = 198

-6a -9c = -210

----------------------

     -c = -12

Multiply by -1

        c = 12

A childs ticket costs 12 dollars

Now we need to find the price of an adult ticket

2a + 3c = 70

2a + 3(12) = 70

2a +36 = 70

Subtract 36 from each side

2a +36-36 =70-36

2a = 34

Divide by 2

2a/2 = 34/2

a = 17

An adult ticket is 17