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Finding the Fourth Proportional to 639.79, 882.15 and 418.66

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Solution

The fourth proportional to 639.79, 882.15 and 418.66 is: 577.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.79 : 882.15 = 418.66 : x
  2. Step 2: Convert to fraction form
    639.79/882.15 = 418.66/x
  3. Step 3: Cross multiply
    639.79x = 882.15 × 418.66
  4. Step 4: Simplify right side
    639.79x = 369,320.92
  5. Step 5: Solve for x
    x = 369,320.92/639.79
  6. Step 6: Final answer
    x = 577.25

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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.