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44 votes
The first term of an arithmetic sequence is -140 and the 90th term is 483. What is the value of the 55th term?

User Farwa
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1 Answer

13 votes
13 votes

Answer: 238

Explanation:

The formula to calculate the nth term of an arithmetic progression = a + (n-1)d

Based on the question,

a = -140

90th term = a + 89d = 483

We need to get the value of the common difference

a + 89d = 483

-140 + 89d = 483

89d = 483 + 140

89d = 623

d = 623/89

d = 7

Therefore 55term will be:

= a + (n - 1)d

= a + (55 - 1)d

= a + 54d

= -140 + 54(7)

= -140 + 378

= 238

User Skyshine
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