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Finding the Fourth Proportional to 639.36, 881.28 and 406.32

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Solution

The fourth proportional to 639.36, 881.28 and 406.32 is: 560.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.36 : 881.28 = 406.32 : x
  2. Step 2: Convert to fraction form
    639.36/881.28 = 406.32/x
  3. Step 3: Cross multiply
    639.36x = 881.28 × 406.32
  4. Step 4: Simplify right side
    639.36x = 358,081.69
  5. Step 5: Solve for x
    x = 358,081.69/639.36
  6. Step 6: Final answer
    x = 560.06

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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.