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Question

The value of$ \sqrt{ 90+\sqrt{(97 + \sqrt{4+(19+\sqrt{(36)}))}}}$ is:

The correct answer is
10

Derive Nested Square Root Value

We need to find the value of the expression:

$ \sqrt{ 90+\sqrt{(97 + \sqrt{4+(19+\sqrt{(36)})})}} $

We will first simplify the expression by calculating from the innermost part outwards.

Step-by-Step Simplification

  1. Innermost square root: $ \sqrt{36} = 6 $
  2. Substitute the result into the next expression: $ 19 + 6 = 25 $
  3. Calculate the next square root: $ \sqrt{4 + 25} = \sqrt{29} $
  4. Substitute this result into the next expression: $ 97 + \sqrt{29} $
  5. Calculate the outermost square root: $ \sqrt{90 + (97 + \sqrt{29})} = \sqrt{187 + \sqrt{29}} $

The expression simplifies to $ \sqrt{187 + \sqrt{29}} $.

Verification Toward Answer 10

Let's check if this expression equals the given answer, 10, by working backward.

  1. Assume the value is 10: $ \sqrt{ 90+\sqrt{(97 + \sqrt{4+(19+\sqrt{36})})}} = 10 $
  2. Square both sides: $ 90+\sqrt{(97 + \sqrt{4+(19+\sqrt{36})})} = 10^2 = 100 $.
  3. Isolate the remaining square root: $ \sqrt{(97 + \sqrt{4+(19+\sqrt{36})})} = 100 - 90 = 10 $.
  4. Square both sides: $ 97 + \sqrt{4+(19+\sqrt{36})} = 10^2 = 100 $.
  5. Isolate the next radical: $ \sqrt{4+(19+\sqrt{36})} = 100 - 97 = 3 $.
  6. Square both sides: $ 4+(19+\sqrt{36}) = 3^2 = 9 $.
  7. Isolate the term $ 19+\sqrt{36} $: $ 19+\sqrt{36} = 9 - 4 = 5 $.
  8. Evaluate $ \sqrt{36} $ directly: $ \sqrt{36} = 6 $.
  9. Substitute this value into the equation from the previous step: $ 19 + 6 = 5 $. This leads to $ 25 = 5 $.

The step $ 25 = 5 $ is mathematically incorrect. This contradiction indicates that the provided numbers in the expression do not lead to the answer 10. The standard simplification results in $ \sqrt{187 + \sqrt{29}} $. However, following the structure common in such problems, the intended derivation might rely on intermediate steps simplifying to integers.

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Important Questions from Simplification

  1. Simplify the following expression.

    \(\left(\frac{7}{16} \div \frac{1}{2}\:of\: \frac{1}{5}\right)\times \frac{4}{5}-\frac{1}{3}\times\frac{5}{8}\div \frac{1}{2}+\frac{3}{4}\)

  2. The value of \(\left( {2\frac{6}{7}of4\frac{1}{5} \div \frac{2}{3}} \right) \times 5\frac{1}{9} \div \left( {\frac{3}{4} \times 2\frac{2}{3}of\frac{1}{2} \div \frac{1}{4}} \right)\)  is:

  3. The value of \(\left[ {\frac{4}{7}\rm \;of\;2\frac{4}{5} \times 1\frac{2}{3} - \left( {3\frac{1}{2} - 2\frac{1}{6}} \right)} \right] \div \left( {3\frac{1}{5} \div 4\frac{1}{2}\;\rm of\;\;5\frac{1}{3}} \right)\)  is:

  4. The value of \(\frac{{0.0203 \times 2.92}}{{0.7 \times 0.0365 \times 2.9}} \div \frac{{{{\left( {12.12} \right)}^2} - {{\left( {8.12} \right)}^2}}}{{{{\left( {0.25} \right)}^2} + \left( {0.25} \right)\left( {19.99} \right)}}\)  is:

  5. The value of 4 ÷ 12 of [3 ÷ 4 of {(4 - 2) × 6 ÷ 2}] - 2 × 6 ÷ 8 + 3 is:

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