Find the sum of the 1st 100 terms: 100+98+96+
50
100
-98
1000

100

Step-by-step explanation:

Given :

Terms ( n ) = 100

First term ( a ) = 100

Series = > 100 + 98 + 96

Common difference ( d ) = 98 - 100 = > - 2

We know sum formula:

S_n = ( n / 2 ) ( 2 a + ( n - 1 ) d )

= > S_100 = ( 100 / 2 ) ( 200 + ( 100 - 1 ) - 2 )

= > S_100 = 50 ( 200 - 198 )

= > S_100 = 50 ( 2 )

= > S_100 = 100

Therefore, sum of first 100 terms is 100.

dnji

step-by-step explanation:

dskfbipo

80π/3 or about 83.775

step-by-step explanation:

since a cone is 1/3 of a cylinder, we need to find the base's area. since area = πr^2, we get 16π. then, multiplying this by 5, we get 80π. dividing by 3, since the cone's volume is 1/3 of that of a cylinder's, we get 80π/3.

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