Answers:
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Explanation:
a = number of apples purchased
c = cost in dollars
The equation is in the form c = ka, where k is the constant of proportionality. It tells us what to multiply 'a' by to get the cost c. In more realistic practical terms, the value of k is the cost per apple (aka unit cost).
To find this unit price, we divide the given price by the given number of apples: k = c/a = 28/14 = 2. Each apple is $2. The constant of proportionality is 2.
We'll update the equation from c = ka to c = 2a
Note that if we bought a = 14 apples, then it costs us c = 2a = 2*14 = 28 dollars as expected.