Speed, Time, Distance Important Formula, Shortcuts & Tricks Pdf - 1

Ans: B

Time taken to travel 45 km = $$({45}/{20})$$hr = $${9}/{4}$$hr = $$2{1}/{4}$$hr = 2 hr 15 min.

Remaining time = (3 hr - 2hr 15 min) 45 min

Hence, required speed = $$({45}/{45})$$km/min = 1 km/min.

Ans: C

Speed of Ramesh = 10 kmph

Ramesh will take rest four times during his journey

∴ Required time = $$(5 ×{1}/{10} × 60)$$minutes + (5 × 4)minutes

= 30 + 20 minutes = 50 minutes

Ramesh takes time to cover a distance of 5 kms.

Ans: A

Time taken to cover 60 miles = 80 min = $${4}/{3}hrs$$.

∴ Speed of the train = $$(60 × {3}/{4}) mph$$ = 45 mph.

Speed of the aeroplane = (2 × 45) mph = 90 mph.

Distance covered by the aeroplane in 60 min = 90 miles.

Distance covered by the aeroplane in 20 min = $$({90}/{60} × 20)$$ = 30 miles.

Ans: C

Speed of the train $$({1125}/{15})$$km/hr = 75 km/hr.

Speed of the bus = $$({1}/{3} × 75)$$km/hr = 25 km/hr.

Distance covered by the bus in 60 min = 25 km.

Distance covered by the bus in 36 min = $$({25}/{60} × 36)km$$ = 15 km.

Ans: B

Relative speed of the thief and policeman = (11 - 10) = 1 km/hr.

Distance covered in 6 minutes = $$({1}/{60} × 6)$$km = $${1}/{10}$$ km = 100 m.

∴ Distance between the thief and policeman = (200 - 100) = 100 m.