The 10th term of the A.P. 1, 5, 9, 13, . . ., is:

The correct answer is Option (3) → 37

In an arithmetic progression each term is the previous one plus the common difference \(d\), so the \(n\)th term is \(a_n=a+(n-1)d\): the first term plus \(n-1\) steps of \(d\).

• First term \(a=1\); common difference \(d=5-1=4\)

• 10th term \(=1+(10-1)\times4=1+36=37\)

Tip: The 10th term is reached in 9 steps, not 10, from the first term. Taking 10 steps gives \(1+40=41\), which is Option (4).