"...on the way to Gauguin's Montemarte studio I noticed the startling variety of sunflowers that lurched through the picket fence. Some so tall and majestic praising the sun, others forlorn and sickly barely putting out a half dozen petals... I wondered: Why aren't they all the same size? Is there something about the quality of the soil that leads to such differences?"
VanGogh then carries out an experiment testing the effect of soil quality. This is used to explain concepts such as independent and dependent variables, null and alternative hypotheses, and sample and population.
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