# Mathematics

If the 8th term of an AP is 36 and the 16th term is 68.
Find:
a) the first term
b) the common difference
c) The 20th term

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1. (b) clearly d=4, since
T16-T8 = 8d = 32

Now do (a) and (c)
For (c), note that T20-T16 = 4d

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