The third term of an Ap is 18 And 7th term 30. Find 17th term.
Answers
Answered by
31
Hey !!
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Let a be the first term and d be the common difference
Then
According to the question !!!!
a + 2d = 18 (1)
a + 6d = 30 (2)
from 1 and 2
4d = 12
d = 3
Substitute it in 1
a + 6 = 18
a = 12
so 17 term
a + 16d = 12 + 16×3 = 12 + 48 = 60
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-----------------------
Let a be the first term and d be the common difference
Then
According to the question !!!!
a + 2d = 18 (1)
a + 6d = 30 (2)
from 1 and 2
4d = 12
d = 3
Substitute it in 1
a + 6 = 18
a = 12
so 17 term
a + 16d = 12 + 16×3 = 12 + 48 = 60
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Answered by
15
a3=18
a7=30
a17 =?
a3 =a+2d
18=a+2d
a+2d =18.....eqn 1.
a7 =a+6d
30=a+6d
a+6d=30. ....eqn 2.
Add eqn 1 and 2
a+2d=18
a+6d = 30
d=3
Substitute value of d in eqn 1
a+2d =18
a+2(3)=18
a=12
a17 =a+1 6d
a17 =12 +16 (3)
a17 =12+48
a17 =60
a7=30
a17 =?
a3 =a+2d
18=a+2d
a+2d =18.....eqn 1.
a7 =a+6d
30=a+6d
a+6d=30. ....eqn 2.
Add eqn 1 and 2
a+2d=18
a+6d = 30
d=3
Substitute value of d in eqn 1
a+2d =18
a+2(3)=18
a=12
a17 =a+1 6d
a17 =12 +16 (3)
a17 =12+48
a17 =60
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