CUET UG 2025 — General Test Arithmetic

P covers his journey in three parts at different speeds. Average speed is calculated as Total Distance ÷ Total Time.

Assume the total journey = 120 km (chosen as the LCM of 5, 6, and 40 to avoid decimals).

---

Part 1: $\dfrac{2}{5}$52​ of journey

Distance $= \dfrac{2}{5} \times 120 = 48$=52​×120=48 km

Part 2: $\dfrac{1}{8}$81​ of journey

Distance $= \dfrac{1}{8} \times 120 = 15$=81​×120=15 km

Part 3: Remaining portion

Remaining $= 1 - \dfrac{2}{5} - \dfrac{1}{8}= \dfrac{19}{40}$=1−52​−81​=4019​

Distance $= \dfrac{19}{40} \times 120 = 57$=4019​×120=57 km

Total Distance $= 48 + 15 + 57= 120$=48+15+57=120 km

---

Time for each part using Time $= \dfrac{\text{Distance}}{\text{Speed}}$=SpeedDistance​:

Part 1: Time $= \dfrac{48}{20} = 2.4$=2048​=2.4 hours

Part 2: Time $= \dfrac{15}{5} = 3$=515​=3 hours

Part 3: Time $= \dfrac{57}{19} = 3$=1957​=3 hours

Total Time $= 2.4 + 3 + 3 = 8.4$=2.4+3+3=8.4 hours

---

Average Speed $= \dfrac{\text{Total Distance}}{\text{Total Time}}$=Total TimeTotal Distance​

$= \dfrac{120}{8.4}\approx 14.28$=8.4120​≈14.28 km/h (option 2).