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Urgent help needed fast-example-1
User Nirav Joshi
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1 Answer

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8 votes

Answer:

Below

Explanation:

You can use this formula to find the sum of an arithmetic series

Sn = n / 2 (a1 + an)

You need to find the number of terms in each series before using the formula

Tn = a + (n - 1) d

a) 53 = 5 + (n - 1) 3

n = 17

Sn = 17 / 2 (5 + 53)

= 493

b) 98 = 7 + (n - 1) 7

n = 14

Sn = 14 / 2 (7 + 98)

= 735

c) -102 = 8 + (n - 1) -5

n = 23

Sn = 23 / 2 (8 + (-102))

= - 1081

d) 41/3 = 2/3 + (n - 1) 1

n = 14

Sn = 14 / 2 (2/3 + 41/3)

= 301 / 3 or 100 1/3

Hope this helped! Best of luck <3

User Zsolt Meszaros
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