A can complete a work in 20 days. B can complete the same task in 15 days. B worked for 10 days and left the job. In how many days A alone can complete the work?

B:s 10 days work=(1/15)*10

=2/3

Remaining work=(1-2/3)=1/3

Now,1/20 work is done by A in 1 day.

Hence ,1/3 work is done by A in (20*1/3)=6.6

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In following questions, a sequence of groups of alphabets and numbers is provided with one term missing , Choose the missing term from options. C4X, F9U, 116R, ?

The first letter of each term is moved three steps forward and the last letter is moved three steps backward to obtain the corresponding letters of the next term.

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The ages of three sisters are in proportion 6x,7x,8x. After six years the sum of their ages is 50. Find their present ages?

Let their present ages be 6x,7x,8x.

Then , (6x+6)+(7x+6)+(8x+6)=50

21x+18=50

21x=50-18

21x=32

x=2

So, their present ages be 12,14,16.

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Look at this series: 1000, 200, 40, ...

What number should come next?

What number should come next?

This is a simple division series.

Each number is divided by 5.

Rule = (1st number / 5 = 2nd number), (2nd number / 5 = 3rd number),...

Now in our case,

(1000 / 5 = 200), (200 / 5 = 40), (40 / 5 = 8)...

So answer is 8..

The cost price of 10 articles is exactly the same as that of selling price of x articles. If profit is 25%, then value of x is ?

C.p of each article is 1 and c.p of x article is x.

S.p of x articles is=10

Profit=RS.(10-x)

So,

(10-x)/x*100=25

1000-100x=25x

125x=1000

Hence=8

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In following number series, two terms have been put within brackets. Choose the appropriate option

Choose the appropriate option (2), 5, (12), 25, 41, 61

Choose the appropriate option (2), 5, (12), 25, 41, 61

The correct sequence is + 4, + 8, + 12, + 16, + 20.

Clearly, 2 is wrong and must be replaced by (5 - 1) i.e. 4.

Also, 12 is wrong and should be replaced by (5 + 8) i.e. 13..