1. Start your equation by making lines like this
- = -
2.On the top right side put x
3.On the bottom right side put 85
4. On the top left side put 3
5.On the bottom left side put 100
6. It should look like this
3 = x
- -
100 85
7. Cross multiply ( 100 times x equals 100x and 3 times 85 is 253 )
8. Divide both by 100 (100x divided by 100 equals 1x and 253 divided by 100 is 2.53)
9. Add 2.53 to 85 (getting 87.53)
10. The answer is: The cost of their TV service is $87.53