[
  "Let Ben = B. Aisha = 2B - 10. Clara = B + 20. Total = 190.",
  "Combine: (2B - 10) + B + (B + 20) = 4B + 10 = 190.",
  "4B = 180, B = 45. Aisha = 2(45) - 10 = 80 dollars."
]