Without using mathematical tables or a calculator, find the exact value of

      

$\frac{28 \times 5.54 + 72 \times 5.54}{7.77^2 - 2.23^2}$

  

Answers

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= $\frac{5.54(28 + 72)}{(7.77 + 2.23)(7.77 -2.23}$

= $\frac{554}{100(5.54)}$

= 1

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raphael answered the question on January 16, 2017 at 07:43

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