{
    "hints":  [
                  "Let a magazine cost 1 unit. A book costs 2 units.",
                  "Total book cost = 5 books x 2 = 10 units. Total magazine cost = 4 x 1 = 4 units.",
                  "Ratio = 10:4 = 5:2 = 2.5 times."
              ]
}