The common difference of the arithmetic sequence is:
4
We kn ow that if the first term of an arithmetic sequence is a and d is the common difference of the sequence then the nth term of the sequence is given by the formula:
[tex]a_n=a+(n-1)d[/tex]
Here we are given:
[tex]a=-3[/tex]
and
[tex]a_15=53\\\\i.e.\\\\a+(15-1)d=53\\\\i.e.\\\\a+14d=53[/tex]
Now using the value of a we have:
[tex]-3+14d=53\\\\i.e.\\\\14d=56\\\\i.e.\\\\d=4[/tex]
