Answer: 80
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Step-by-step explanation:
5624 is close to 5600
72 is close to 70
Therefore, 5624 ÷ 72 is close to 5600 ÷ 70 = 80
Think of it like saying 56 ÷ 7 = 8 but then we add the zeros onto each to get what is shown above.
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Use your calculator to find that
5624 ÷ 72 = 78.111 approximately
which isn't too far from the estimate value of 80. Our estimate is an over-estimate.