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Finding the Fourth Proportional to 642.13, 886.34 and 509.09

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Solution

The fourth proportional to 642.13, 886.34 and 509.09 is: 702.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.13 : 886.34 = 509.09 : x
  2. Step 2: Convert to fraction form
    642.13/886.34 = 509.09/x
  3. Step 3: Cross multiply
    642.13x = 886.34 × 509.09
  4. Step 4: Simplify right side
    642.13x = 451,223.67
  5. Step 5: Solve for x
    x = 451,223.67/642.13
  6. Step 6: Final answer
    x = 702.70

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.