A Boat covers a distance of 30 km downstream in 2 hours while it takes 6 hours to cover the same distance upstream. What is the speed of the boat in kilometre per hour?

Let B and S be the speed of boat and stream respectively

As per the given conditions

30/(B+S)=2

30/(B-B)=6

From eq (i) and (ii):

S=5 ,b= 10 km/hr

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In alphabet series, some alphabets are missing which are given in that order as one of the alternatives below it. Choose the correct alternative. c _ baa _ aca _ cacab _ acac _ bca

The series is cab / aa / cacab / cacab / aa / cacab / ca. Thus, the pattern cacab, cacab, aa is repeated

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Kim spent half of her weekly allowance playing mini golf . To earn more money her parents let her wash the car for Dollar 4 . What is her weekly allowance if she ended up with dollar 12?

She had dollar 12 after She washed the car for Dollar 4,so before she washed the car, she had dollar 8 and that was after she had spent 1/2 her allowance. 2 x 8 = 16

Her allowance is dollar 16.

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Alvin travelled from his town to city. Alvin went to city by bicycle at a speed of 25 km per hour and came back at a speed of 4 km per hour. If element took 5 hours and 48 minutes to complete his journey, what is the distance between town and city?

Average speed of Alvin=2xy/x+y=2x25x4/25+4=200/29km/hr

Distance travelled i= speed x time

= 200/29x 29/5= 40 km

Distance between city and town= 40/2= 20 km

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