35. An arithmetic progression consists of 37 terms. The sum of the first 3 terms of
it is 12 and the sum of its last 3 terms is 318, then find the first and last terms
of the progression.
OR
Answers
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Step-by-step explanation:
let the first three terms be
a-d, a, a+d
then last terms will be a-d+(37-1)d, a-d+(36-1)d, a-d+(35-1)d.
sum of first terms is given and is equal is 12
a-d+a+a+d=12
3a=12,
a=4 -----eq1
also sum of last three terms is 318
a+35d+a+34d+a+33d=318
3a+102d=310,
put the value of a from eq1
12+102d=310
102d=310
d=298/102.
d=2.921
first three terms are a-d, a, a+d = 1.078, 4, 6.921
last three terms are a+33d, a+34d, a+33d = 4+33*2.921 solve it calculator please
hope it helps
take care
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