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Finding the Third Proportional to 4.20 and 9.01

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Solution

The third proportional to 4.20 and 9.01 is: 19.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.20 : 9.01 = 9.01 : x
  2. Step 2: Convert to fraction form
    4.20/9.01 = 9.01/x
  3. Step 3: Cross multiply
    4.20x = 9.01 × 9.01
  4. Step 4: Simplify right side
    4.20x = 81.21
  5. Step 5: Solve for x
    x = 81.21/4.20
  6. Step 6: Final answer
    x = 19.36

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Why These Related Problems?

These problems maintain the same ratio (2.15) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.