You can use the roots of the words to help you remember the difference. Quantitative has to do with numbers, like the word quantity. Quantitative research measures things with numbers. How many people like coffee? How many trees fell over in the storm? How many books do people read each year? You then take these numbers and maybe do some statistics or other math to come to a conclusion. Qualitative research has to do with looking at qualities. Maybe you taste a bunch of coffees and compare them in some way. Maybe you talk to people about their experience during a big storm and compile a report about how different people reacted to the stressful situation. Have a bunch of people read a book and describe it. These are all about qualities of things, and generally don't use numbers. Quantitative => Quantity => Research using numbers and math. Qualitative => Quality => Research using opinions and experiences, generally not using numbers. More on reddit.com

This is a very simplified answer but If you offered options for answers (what is your favorite color? A. Blue B. Green C. Red) you have done quantitative research. You can tally and count quantitative responses. Qualitative research would be if you audio/video recorded an interview with participants asking broader questions about their experiences for example and coded the transcripts to find themes in their answers. Qualitative research is not analyzed statistically but through a coding process of recognizing common experiences across participant accounts. More on reddit.com

No that is absolutely 100% wrong. Those sizes are not quantitative data and mistaking this kind of 'quantitized' data for actual quantitative data is among the most common mistakes in statistics. Data is only really quantitative if there is an actual quantity being measured. Height, weight, number of something, duration. Things like 'rate on a scale from one to ten' are actually quanlitative data masking as quantitative data. There is no scale calibration, no useful sense in which a 4 is 'twice as good' as a 2. One has simply used numbers to create the illusion of measurement. Applying, say, a linear regression to this sort of data is going to be questionable at best, misleading at worst. Now if those sizes weren't made up, but an actual body measurement, like mens pants or suits, then you've got quantitative data. A result of this is that a great deal of statistical reasearch done by amateurs in business contexts is pretty untrustworthy. It is no surprise to me a instructor got this wrong. I'm honestly very impressed you saw through it. Most people actually believe throwing numbers into something makes it magically rigorous. You are now definitely smarter than most MBAs! More on reddit.com

In very basic terms - are your results numbers or words. Numbers =quant. Words = qual. More on reddit.com