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Finding the Fourth Proportional to 639.12, 882.28 and 418.08

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Solution

The fourth proportional to 639.12, 882.28 and 418.08 is: 577.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.12 : 882.28 = 418.08 : x
  2. Step 2: Convert to fraction form
    639.12/882.28 = 418.08/x
  3. Step 3: Cross multiply
    639.12x = 882.28 × 418.08
  4. Step 4: Simplify right side
    639.12x = 368,863.62
  5. Step 5: Solve for x
    x = 368,863.62/639.12
  6. Step 6: Final answer
    x = 577.14

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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.