Problem: xavier starts from p towards q at a speed of 90 kmph and after every 12 mins increases his speed by 20 kmph . if the distance between p and q is 61 km , then how much time does he take to cover the distance ?
Rationale: "first 12 min = 90 * 12 / 60 = 18 km 2 nd 12 min = 110 * 12 / 60 = 22 km 3 rd 12 min = 130 * 12 / 60 = 26 km total time 12.3 = 36 min e"
annotated_formula: add(add(add(12, 12), 12), 12)