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Finding the Fourth Proportional to 639.45, 882.23 and 406.71

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Solution

The fourth proportional to 639.45, 882.23 and 406.71 is: 561.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.45 : 882.23 = 406.71 : x
  2. Step 2: Convert to fraction form
    639.45/882.23 = 406.71/x
  3. Step 3: Cross multiply
    639.45x = 882.23 × 406.71
  4. Step 4: Simplify right side
    639.45x = 358,809.73
  5. Step 5: Solve for x
    x = 358,809.73/639.45
  6. Step 6: Final answer
    x = 561.12

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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.