A boat man goes 4 Km against the current of the stream in 1hour and goes 2 Km along the current in 5 minutes. How long will it take to go 21 Km in stationary water

- A1 Hour
- B1 Hour 15 Minutes
- C1 Hour 30 Minutes
- D1 Horr 45 Minutes

In an hour a boat goes 10 Km along the stream and 4 Km against the stream. The speed of the boat in still water (in Kmph) is:

- A7 Kmph
- B8 Kmph
- C6 Kmph
- D10 Kmph
**Explanation:**speed of stream = X Kmph

and the speed of water = 8 Kmph

X + Y = 10

X - Y = 4

X = 7, Y = 3

Speed of stream = 7 Kmph

A man can row 8 Kmph in still water. If the velocity of the current is 2 Kmph and it takes him 2 hours to row to a place and come back. How far is the place

- A6.5 km
- B7.5 km
- C7.4 km
- D6.4 km
**Explanation:**8 + 2 = 10 kmph

8 - 2 = 6 kmph

required distance be X km

Then X/10+X/6 = 2

3X + 5X = 60

8X = 60

X = 7.5 km

A man rows to a place 48 Km distance and back in 14 hours. He finds that he can row 4 Km with the stream in the same time 3 Km against the stream. The rate off the stream is

- A1 kmph
- B2 kmph
- C1.5 kmph
- DNone
**Explanation:**48/4/X + 48/3/X = 14

12X + 16X =14

X = 1/2

Speed in downstream = 8 Kmph

Speed in up stream = 6 Kmph

Then the Rate of stream = 1/2 (8 - 6) = 1 Kmph

In a stream running at 2 Kmph, a motor boat goes 10 Km upstream and back again to the starting point in 55 minutes. Find the speed of motor boat in still water

- A18 kmph
- B22 kmph
- C16 kmph
- D20 kmph
**Explanation:**speed in downstream = (X + 2) km

speed in upstream = (X - 2) kmph

10/X+2 + 10/X-2 = 55/60

11X2 - 240X - 44 = 0

(X - 22)(11x + 2) = 0

X = 22 or X = -2/11

Then X = 22 kmph

A man can row 24 kmph in still water. It takes him thrice as long to row up as to row down the river. Find the rate of the stream?

- A4 kmph
- B12 kmph
- C6 kmph
- D1 kmph
**Explanation:**Rate of upstream = X kmph

Rate of down stream = 3 x kmph

Rate of still water = (3x+x)2 = 2x

2x = 24

x = 12

Rate of upstream = 12

Rate of downstream = 36

Rate of stream = 36-12/2 = 12 kmph

Categories

Alligation or MixtureAnalytical ReasoningAreaArithmetic AptitudeAverageBanker's DiscountBoats & StreamCalendarChain RuleCompound InterestDecimal FractionGeometryHeight and DistanceLogarithmMental AbilityNumbersOdd Man Out and SeriesPartnershipPercentagePermutation and CombinationPipes and CisternProbabilityProblems on AgeProblems on ClocksProblems on H.C.F and L.C.MProblems on NumbersProblems on TrainsProfit and LossRaces and GamesRatio and ProportionReasoningSimple InterestSimplificationSquare Root and Cube RootStocks and SharesSurds and IndicesTime and DistanceTime and WorkTrue DiscountVolume and Surface Area