Question

the 21st term of A.P.3,8,13........is

Answer 1

hey mate here is your answer

AP=3,8,13,..........

so a=first term=3

and d= common difference=a2-a1

=8-3

=5

so by using an=a + ( n-1 )d

a21=3+(21-1)5

a21=3+20×5

a21=3+100

a21=103

hope it will help you

mark me brainliest ✌✌✌✌

Answer 2

Given sequence : 3 , 8 , 13 ....

Now,
First term = a = 3
Second term = a + d = 8
Common difference = ( a + d ) - a = 8 - 3 = 5


We know ( formula) ,
zth term = a + ( z - 1 )d , where a is the first term, d is the common difference and z is the Number of terms.


Now,
21st term = a + ( 21 - 1 )d
= > 3 + ( 21 - 1 )5
= > 3 + ( 20 x 5 )
= > 3 + 100
= > 103


Therefore, 21st term of the AP is 103

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