Answer
$847$
Work Step by Step
Here, we have $a_{14}=1+(14-1)(-3-1)=-51$
and $b_{14}=3+(14-1)(8-3)=68$
The sum of an arithmetic sequence is given by: $S_n=\dfrac{n}{2}[a_1+a_n]$
Now, $\sum_{i=1}^{14}b_i-\sum_{i=1}^{14} a_i=\dfrac{14}{2}(3+68)-\dfrac{14}{2}(1-51)$
Thus, $\sum_{i=1}^{14}b_i-\sum_{i=1}^{14} a_i=847$