Find the sum of series 1+3+....+51. Then Find the 32nd term of series 3, 7, 11, .... then A and B can do a wo

Question

rk in 12 days. If A can do it in 18 days, how long will B take to do the work? Then wat is the formula to find area of circle and triangle? Then a player in 50 games gained Rs. 7 per win and lost Rs. 5 per loss. In all he won Rs. 2. How many games did he win? If formulas used for any of the questions, please lemme know those formulas too. Thanks in advance...

Answer 1

Your doing this just to bug people arent u??

Anyways:

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Sum of a series = n/2 (a +(n-1)d)

a= first term.

n= ( last term - first term)/ d

d= difference between any two terms.

therefore : d= 2, n = 25, sum= 650

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nth term of a series = (a + (n-1)*d)

here a = 3

d= 7 - 3 = 4

therefore 32nd term is

= 3 + 31* 4

=127

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The work done by A & B together per day is 1/12

The work done by A alone per day is 1/18

Let the work done by B per day be x.

=> 1/12 = 1/18 + x

=> x = 1/36

so B takes 36 days to complete the work.

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Area of a circle = pi * r ^2 (r= radius of the circle)

Area of a triangle

= 1/2 * base * height

OR

= square root of (s * (s-a) * (s-b) * (s-c) )

where a,b and c are the lenghts of three sides and s is the semi perimeter ( s= (a+b+c)/2 ).

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Let the number of times he wins be x.

=> 7x - (50 -x)*5 =2

=>x=21

Ans : he wins 21 times and looses 29 times.