100+ Boats and Streams Aptitude Questions and Answers Pdf - 1

Question: 1

The speed of a boat in still water is 15 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 12 minutes is

(A) 2.4 km

(B) 3.6 km

(C) 4.8 km

(D) 5.1 km

Ans: B

Speed downstream = (15 + 3) kmph = 18 kmph.

Distance travelled = $$(18 × {12} / {60})$$ km = 3.6 km.

Question: 2

Speed of a man is 19 Km/h in still water. If the rate of current is 3 Km/h, then the effective speed of the man upstream is

(A) 6 Km/hr

(B) 7 Km/hr

(C) 9 Km/hr

(D) 10 Km/hr

Ans: B

Speed of man in still water = 10 Km/hr

Speed of current = 3 Km/hr

∴ Speed of man upstream = 10 – 3 = 7 Km/hr.

Question: 3

A boatman goes 2 Km against the current of the stream in 1 h and goes 1 Km along the current in 10 min. How long will he take to go 5 Km in stationary water?

(A) 1 hour

(B) 1.5 hour

(C) 1 hour 15 minutes

(D) 40 minutes

Ans: C

Upstream speed = 2 km/hr

Downstream speed = 6 km/hr

∴ Speed in still water = $${2 + 6} / {2}$$ = 4 km/hr.

∴ Time required to go 5 km in still water = $${5} / {4}$$ hours = 1 hours 15 minutes.

Question: 4

A man’s speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man’s speed against the current is

(A) 8 km/hr

(B) 8.5 km/hr

(C) 9 km/hr

(D) 10 km/hr

Ans: D

Man’s rate in still water = (15 – 2.5) km/hr = 12.5 km/hr.

Man’s rate against the current = (12.5 – 2.5) km/hr = 10 km/hr.

Question: 5

A man can row upstream at 7 kmph and downstream at 10 kmph. Find man’s rate in still water and the rate of current.

(A) 1.2 km/hr

(B) 1.5 km/hr

(C) 1.8 km/hr

(D) 2.1 km/hr

Ans: B

Rate in still water = $${1} / {2}$$(10 + 7) km/hr = 8.5 km/hr.

Rate of current = $${1} / {2}$$ (10 -7) km/hr = 1.5 km/hr.

Error Report!

Related Questions