The possible ways to do it should be: 1. 0 group of "10 rocks" 38 group of single rock 2. 1 group of "10 rocks" 28 group of single rock 3. 2 group of "10 rocks" 18 group of single rock 4. 3 group of "10 rocks" 8 group of single rock
Website A: c = 10 + 0.25 s where c is the cost and s is the number of songs. Website B: c = 0.75 s The equation ( answer ): 10 + 0.25 s = 0.75 s We can solve this equation: 10 = 0.5 s s = 10 : 0.5 s = 20 ( Marvin would have to buy 20 songs to to make the costs equal )
