Question

1. (a) Calculate 1 - 2 - 3 - 4 - 5 - 6 + ..... + 179 - 180.
(b) Find the value of 5 + (-5) + 5 + (-5) + 5 + ...... if the number of fives are=
(I)148
(ii) 191​

Answer 1

Answer:

148.....

Step-by-step explanation:

I hope u will get it......

Answer 2

(a) answer:

S =   1 - 2 + 3 - 4 + 5 - 6 + ___ + 179 - 180

+   S =       1 - 2 + 3 -  4 + 5 - 6 + ___ + 179 - 180

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2S =           1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - ___ - 1 - 1 - 1 - 180

2S = -180

S =  

S = -90

(b) answer:

  5 + (– 5) + 5 + (– 5) + 5 ......

=  (5 – 5) + (5 – 5) + 5........

=   0 + 0 + 0 + 0 + 5......

=   5

Number of 5 in [5 + (– 5) + 5 + (– 5) + 5] is five.

AND five is an odd number.

and it's soluction is 5.

 

   5 + (– 5) + 5 + (– 5) + 5 + (- 5) ......

=  (5 – 5) + (5 – 5) + (5 – 5).......

=  0    

Number of 5 in [5 + (– 5) + 5 + (– 5) + 5 + (- 5)] is Six.

AND six is even number.

and it's soluction is 0.

We observed that, when number of five is odd answer = 5

and when it is even answer = 0

question 1.) 148

148 is even number then, answer = 0

question 2.) 191

191 is an odd number then, answer = 5