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Finding the Fourth Proportional to 639.65, 882.39 and 418.69

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Solution

The fourth proportional to 639.65, 882.39 and 418.69 is: 577.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.65 : 882.39 = 418.69 : x
  2. Step 2: Convert to fraction form
    639.65/882.39 = 418.69/x
  3. Step 3: Cross multiply
    639.65x = 882.39 × 418.69
  4. Step 4: Simplify right side
    639.65x = 369,445.78
  5. Step 5: Solve for x
    x = 369,445.78/639.65
  6. Step 6: Final answer
    x = 577.57

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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.