Simple volume flow rate calculation

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The discussion centers on calculating the volume flow rate in a pipe with varying diameters and speeds. The user initially struggles with the formula, believing that combining the areas and speeds might be necessary. It is clarified that the volume flow rate can be calculated using the formula Q = Av for each segment, ensuring that the radius is used instead of diameter. The user realizes a mistake in unit conversion, which led to incorrect answers. Ultimately, consistent application of the formula across all segments should yield the same volume flow rate.
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[SOLVED] Simple volume flow rate calculation

A 1.0-cm-diameter pipe widens to 2.0 cm, then narrows to 0.5 cm. Liquid flows through the first segment at a speed of 4.0m/s. The speed in the second segment is 1m/s, and the speed in the 3rd segment is 16 m/s

I thought that volume flow rate was simply Av, but I've tried many combinations of the 3 cross-sectional areas and 3 speeds with no success. Do I need to add them all up and multiply? Do I need to take averages? Oh, and should I have my units in terms of meters or centimeters? I'm really baffled as to why my answers aren't working, because I know it's a fairly simple problem. Any help would be appreciated. Thanks
 
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All three should give the same answer when multiplying the area and the velocity. Check your units and that you're using radius not diameter.
 
Got it. I was off by a factor of 10. Thanks
 

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