Question

find the 18 th term of the A.P 4,7,10....​

Answer 1

Given AP:

• 4,7,10...

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To find:

• 18th term of AP

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Solution:

To find the 18th term, we have to obtain the value of a(first term) and d(common difference) of the given AP. So let's find these values and try to solve the problem further.

The first term of AP is 4 as AP is starting from 4.

So,

» First term, a=4

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• Finding common difference

To find the common difference, we have to subtract preceeding term from the succeeding term of AP.

So,

» d, Common difference=a2-a1

» d, Common difference=7-4

» d, Common difference=3

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• Now we have formula for nth term of AP:-

» an=a+(n-1)d

:: Put value of n=18 for 18th term

» a18=a+(18-1)d

:: Put value of a and d

» a18=4+(18-1)(3)

» a18=4+(17)(3)

» a18=4+51

» a18=55

So the required 18th term of AP is 55.

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Answer 2

Step-by-step explanation:

a = 4 , d = 6, n = 18 , t19 = ?

tn = a + ( n - 1 )

t19 = 4+( 18-1 ) × 6

= 4 + 17 ×6

= 4 + 102

= 106

may this answer is help you❤