Question

Adrianna and her friend rode the bus 13 times in a month and it cost $4 for each of them each time. If Arianna always paid for both of them, how much did it cost her for the month?

Answer 1

$104
13x4x2
If she paid for both of them she would pay twice as much as she would for herself, so you can either multiply 13 by 8 or use the equation that I put above.

Answer 2

Add both of their costs which is 4+4=8 then multiply 8 times 13 gives you 104