Question

The 10th and 20th terms of an AP are 73 and 143 respectively. Find the common
difference
and 30th term of AP


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Answer 1

Answer:

d=7, a30=303

Step-by-step explanation:

a10=a+9d=73            (1)

a20=a+19d=143        (2)

by subtracting (1) from (2), we get:

a+19d - a-9d = 143-73

=> 10d = 70

d=7=common difference

using d=7 in (1)

we get a=10

now, a30=10+(30-1)(7)

=10+293=303=a30