Question

Find the A.P. whose 6th term is 25 and 19th term is 77.
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Answer 1

Answer:

5, 9, 13,17

Step-by-step explanation:

6th term is 25

we know nth term of A.P is

tn = a+(n-1)d

so, t6 = a+(6-1)d

a+5d=25 ( 1st equation)

t19 = a+18d

a+18d=77( 2nd equation)

subtract equation 2 from equation 1

we get, -13d = -52

d = -52/-13

d = 4

substitute d=4 in equation 1

a+(5×4)= 25

a+20= 25

a=5

A.P general from is a, a+d, a+2d

so A.P is 5, 9, 13, 17......