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Finding the Fourth Proportional to 639.36, 961.02 and 424.32

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Solution

The fourth proportional to 639.36, 961.02 and 424.32 is: 637.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.36 : 961.02 = 424.32 : x
  2. Step 2: Convert to fraction form
    639.36/961.02 = 424.32/x
  3. Step 3: Cross multiply
    639.36x = 961.02 × 424.32
  4. Step 4: Simplify right side
    639.36x = 407,780.01
  5. Step 5: Solve for x
    x = 407,780.01/639.36
  6. Step 6: Final answer
    x = 637.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.