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Finding the Fourth Proportional to 639.42, 882.60 and 406.68

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Solution

The fourth proportional to 639.42, 882.60 and 406.68 is: 561.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.42 : 882.60 = 406.68 : x
  2. Step 2: Convert to fraction form
    639.42/882.60 = 406.68/x
  3. Step 3: Cross multiply
    639.42x = 882.60 × 406.68
  4. Step 4: Simplify right side
    639.42x = 358,935.77
  5. Step 5: Solve for x
    x = 358,935.77/639.42
  6. Step 6: Final answer
    x = 561.35

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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.