Answer: C) 75% increase
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Step-by-step explanation:
We go up by 300,000 since 700,000-400,000 = 300,000
Divide this increase by the original amount
(300,000)/(400,000) = 0.75 = 75%
Therefore, we have a 75% increase.
It might help to ignore the zeros and just think of it like this: "We start at 4 and jump to 7. That's an increase of 3, so we have a 3/4 = 0.75 = 75% increase".