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Finding the Fourth Proportional to 639.56, 961.19 and 424.51

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Solution

The fourth proportional to 639.56, 961.19 and 424.51 is: 637.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.56 : 961.19 = 424.51 : x
  2. Step 2: Convert to fraction form
    639.56/961.19 = 424.51/x
  3. Step 3: Cross multiply
    639.56x = 961.19 × 424.51
  4. Step 4: Simplify right side
    639.56x = 408,034.77
  5. Step 5: Solve for x
    x = 408,034.77/639.56
  6. Step 6: Final answer
    x = 637.99

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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.