In an AP the difference between 16th term and 10th term is 66 and the sum of 1st three terms is 57. Find the first term and the common difference of AP
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don't know the answer sorry dude
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Answer:
First term, a = 8
Common difference, d = 11
Solution:
Tn = a + (n - 1)d
T10 = a + 9d
T16 = a + 15d
(a + 15d) - (a + 9d) = 66
a + 15d - a - 9d = 66
6d = 66
d = 11
Sn = n/2 [2a + (n - 1)d]
57 = 3/2 [2a + (3 - 1)11]
57 = 3/2 [(2a + 2(11)]
57 = 3/2 (2a + 22)
38 = 2a + 22
2a = 16
a = 8
Hope this will be helpful.
First term, a = 8
Common difference, d = 11
Solution:
Tn = a + (n - 1)d
T10 = a + 9d
T16 = a + 15d
(a + 15d) - (a + 9d) = 66
a + 15d - a - 9d = 66
6d = 66
d = 11
Sn = n/2 [2a + (n - 1)d]
57 = 3/2 [2a + (3 - 1)11]
57 = 3/2 [(2a + 2(11)]
57 = 3/2 (2a + 22)
38 = 2a + 22
2a = 16
a = 8
Hope this will be helpful.
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