sure thing marlon. i use my equityfeed account which does the accurate math for me. however many times if it's closed i will just grab the chart and multiply estimates.
for example... in equityfeed IDOI says the following:
volume 39,990,239 $ volume $67,073 trades 226
without equityfeed, you can just pull up a simple stockchart and round up/down on the volume and estimate the average trading price.