determine the AP whose 3rd
term is 10 and and 13th term is 50
Answers
Answered by
0
Step-by-step explanation:
a+2d=10
a+12d=50
10d=40
d=40/10
d=4
a+2*4=10
a+8=10
a=10-8
a=2
Answered by
0
Answer:
A.P. is 2, 6, 10, 14, 18, ......
Step-by-step explanation:
t3 = 10 and t13 = 50 ... Given
tn = a + (n-1) d ..... Formula
t3 = a + (3-1) d
∴ 10 = a + 2d ...... (1)
Similarly,
t13 = a + (13-1) d
∴ 50 = a + 12d ...... (2)
Subtracting equation (1) from equation (2), we get,
50 = a + 12d
- 10 = a + 2d
(-) (-) ..... Signs change
∴ 40 = 10d
∴ d = 40/10
∴ d = 4
Substituting d = 4 in equation (1), we get,
10 = a + 2 (4)
∴ 10 = a + 8
∴ a = 10 - 8
∴ a = 2
A.P. has terms a, a+d, a+2d, .....
Therefore, the A.P. is 2, 6, 10, 14, 18, ......
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