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Finding the Third Proportional to 15.85 and 34.20

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Solution

The third proportional to 15.85 and 34.20 is: 73.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.85 : 34.20 = 34.20 : x
  2. Step 2: Convert to fraction form
    15.85/34.20 = 34.20/x
  3. Step 3: Cross multiply
    15.85x = 34.20 × 34.20
  4. Step 4: Simplify right side
    15.85x = 1,169.60
  5. Step 5: Solve for x
    x = 1,169.60/15.85
  6. Step 6: Final answer
    x = 73.80

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Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.