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Find out sum of all even number in between 1 to 151 |
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Answer» This QUESTION can be solved by using concept of Arithmetic Progression ( AP ). Now, the first EVEN number between 1 to 150 = 2 So, a1 = 2 Last even number between 1 to 150 = 150 So an, = 150 COMMON difference ( d ) = second term - first term = 4 - 2 = 2 We know that an = a+ ( n - 1 ) 150 = 2+(n - 1 )× 2 150 - 2 = ( n - 1 ) × 2 148 = ( n - 1 ) × 2 148 / 2 = n - 1 74 = n - 1 74 + 1 = n 75 = n We know that , SN = n upon 2 ( a + an ) = 75 upon 2 ( 2 + 150 ) = 75 upon 2 × 152 = 75 upon 2 × 152 75 × 76 = 5700 So, sum of all even number between 1 + 150 is 5700. |
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