Final answer:
The constant rate of proportionality in the equation 'y = 6.7x' is 6.7. It shows how much y changes for an increase of 1 in x. Option B is correct.
Step-by-step explanation:
In mathematics, particularly in the equation of a line or a proportionality, the number multiplying the variable x is known as the constant rate of proportionality. In the equation provided by Mr. Allen, y = 6.7x, the constant rate of proportionality would be the number 6.7. This number shows how y changes with respect to x. It signifies that for every increase of 1 in x, y will increase by a factor of 6.7.
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