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Finding the Fourth Proportional to 639.09, 954.30 and 507.61

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Solution

The fourth proportional to 639.09, 954.30 and 507.61 is: 757.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.09 : 954.30 = 507.61 : x
  2. Step 2: Convert to fraction form
    639.09/954.30 = 507.61/x
  3. Step 3: Cross multiply
    639.09x = 954.30 × 507.61
  4. Step 4: Simplify right side
    639.09x = 484,412.22
  5. Step 5: Solve for x
    x = 484,412.22/639.09
  6. Step 6: Final answer
    x = 757.97

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.