Math, asked by raibanff98, 7 hours ago

the fifth term of an arithmetic sequence is 38 and the nineth term is 66 what is its 25th term​

Answers

Answered by itzbangtanbutterfly
11

Answer:

The 5th term of an arithmetic sequence is 38 and 9th term is 66.What is its 25th term.

Given that,

a5 = 38

a9 = 66

We can write these terms as...

a5 → a + 4d = 38... (1)

a9 → a + 8d = 66... (2)

Now, subtract the equations (1) & (2), we get

➡ - 4d = - 28

➡ 4d = 28

➡ d = 7

∴d=7

Now, substitute the value of d in (1)

➡ a + 4(7) = 38

➡ a + 28 = 38

➡ a = 38 - 28

➡ a = 10

∴a=10

To find the value of 25th term,

↪ an = a + (n - 1)d

a = 10

d = 7

n = 25

➡ a25 = 10 + (25 - 1)(7)

➡ a25 = 10 + 24(7)

➡ a25 = 10 + 168

➡ a25 = 178

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Answered by roosey12
2

Answer:

The 5th term of an arithmetic sequence is 38 and 9th term is 66.What is its 25th term.

Given that,

a5 = 38

a9 = 66

We can write these terms as...

a5 → a + 4d = 38... (1)

a9 → a + 8d = 66... (2)

Now, subtract the equations (1) & (2), we get

➡ - 4d = - 28

➡ 4d = 28

➡ d = 7

∴d=7

Now, substitute the value of d in (1)

➡ a + 4(7) = 38

➡ a + 28 = 38

➡ a = 38 - 28

➡ a = 10

∴a=10

To find the value of 25th term,

↪ an = a + (n - 1)d

a = 10

d = 7

n = 25

➡ a25 = 10 + (25 - 1)(7)

➡ a25 = 10 + 24(7)

➡ a25 = 10 + 168

➡ a25 = 178

Step-by-step explanation:

I hope this will help you

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