The sum of even numbers between 1 and 31 is:

16
228
3240
4512

Answer:- 1

Explanation:-

Solution:

Let S_n = (2 + 4 + 6 + ..... + 30). This is an A.P. in which a = 2, d = 2 and l = 30
Let the number of terms be n Then,
a + (n - 1)d = 30
⇒ 2 + (n - 1) x 2 = 30
⇒ n = 15

∴ S_{n} = \frac{n}{2} (a + I) = \frac{15}{2} \times (2 + 30)

$\therefore {S_n} = \frac{n}{2}\left( {a + I} \right) = \frac{{15}}{2} \times \left( {2 + 30} \right)$
= (15 x 16) = 240

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= (15 x 16) = 240 ", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

Let S_n = (2 + 4 + 6 + ..... + 30). This is an A.P. in which a = 2, d = 2 and l = 30
Let the number of terms be n Then,
a + (n - 1)d = 30
⇒ 2 + (n - 1) x 2 = 30
⇒ n = 15

∴ S_{n} = \frac{n}{2} (a + I) = \frac{15}{2} \times (2 + 30)

$\therefore {S_n} = \frac{n}{2}\left( {a + I} \right) = \frac{{15}}{2} \times \left( {2 + 30} \right)$
= (15 x 16) = 240 ", "dateCreated": "7/24/2019 10:09:12 AM" } }