Much of Physics will involve identifying the pattern that exists between variables and using that pattern to predict the value that the independent variable has for any given change in the dependent variable. To make such predictions, you will need to reason proportionally. That is, you will need to understand the concept of doubling, tripling, quadrupling, halving, etc.  That's what this question is all about.
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Reasoning Proportionally
When a physicist looks for patterns in data, they think in terms of multipliers. They typically ask, for any given doubling of X, by what multiple does Y change by? Or for a tripling of X, by what multiple does Y change by? Or for a quadrupling of X,  by what multiple does Y change by? Thinking in this manner is sometimes referred to as proportional reasoning. Finding the pattern of proportionality allows a physicist to make a prediction of the Y value for any given change in the X value.


Using Proportional Reasoning to Predict
This question and most of the questions in this Concept Builder will emphasize the effect of doubling, tripling and quadrupling the value of the independent variable. Such a change will cause the dependent variable to change by the same multiple, the inverse (or reciprocal) multiple, or the squared multiple. In this question we learn that the doubling (or tripling or quadrupling, depending on the question version you get) of the X value will cause the Y value to increase by the same multiple - either doubling, tripling or quadrupling.  To change in this manner means to become two times, three times, or four times the original value. So to predict the unknown value of Y, you will need to take the original value of Y and multiply it by 2, 3 or 4 (depending upon which version of the question you have).