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Finding the Fourth Proportional to 639.90, 955.52 and 508.42

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Solution

The fourth proportional to 639.90, 955.52 and 508.42 is: 759.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.90 : 955.52 = 508.42 : x
  2. Step 2: Convert to fraction form
    639.90/955.52 = 508.42/x
  3. Step 3: Cross multiply
    639.90x = 955.52 × 508.42
  4. Step 4: Simplify right side
    639.90x = 485,805.48
  5. Step 5: Solve for x
    x = 485,805.48/639.90
  6. Step 6: Final answer
    x = 759.19

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.