Answer :
Company A:
c = 40 + 2s
Company B:
c = 20 + 4s
Equal costs => 40 + 2s = 20 +4s => 4s - 2s = 40 - 20 => 2s = 20 => s = 20/2
=> s = 10
And c = 20 + 4s = 20 + 4(10) = 20 + 40 = 60
Answer: 10 videos
c = 40 + 2s
Company B:
c = 20 + 4s
Equal costs => 40 + 2s = 20 +4s => 4s - 2s = 40 - 20 => 2s = 20 => s = 20/2
=> s = 10
And c = 20 + 4s = 20 + 4(10) = 20 + 40 = 60
Answer: 10 videos