The 21st term of an Arithmetic Progression, whose 11th term is 38 and 16th term is 73, will be:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 108
In an AP every term is the one before it plus the common difference \(d\), so terms that are 5 places apart differ by \(5d\). The 11th, 16th and 21st terms are 5 places apart each.
From the 11th to the 16th term: \(5d=73-38=35\), so \(d=7\)
21st term \(=73+5\times7=108\)