Tamil Nadu Board Solutions for Chapter: Numbers And Sequences, Exercise 17: Progress Check

The common difference of a constant$\mathrm{A}.\mathrm{P}.$ is _____.

If $a$ and $l$ are first and last terms of an A.P. and $d$ is the common difference.  If the number of terms is$\frac{l-a}{d}+k$, then $k=$  _____.

If $a$ and $l$ are first and last terms of an A.P. then the number of terms is $\left(\frac{l-a}{d}\right)+$_____.

If every term of an A.P. is multiplied by $3$, then the common difference $\left(d\right)$ of the new A.P. is _____.

Three numbers $a, b$ and $c$ will be in $\mathrm{A}.\mathrm{P}.$, if and only if $2b=$ _____.

Three numbers $a, b$ and $c$ will be in $\mathrm{A}.\mathrm{P}.$, if and only if $a+c=$_____.