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Finding the Fourth Proportional to 639.47, 958.75 and 314.76

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Solution

The fourth proportional to 639.47, 958.75 and 314.76 is: 471.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.47 : 958.75 = 314.76 : x
  2. Step 2: Convert to fraction form
    639.47/958.75 = 314.76/x
  3. Step 3: Cross multiply
    639.47x = 958.75 × 314.76
  4. Step 4: Simplify right side
    639.47x = 301,776.15
  5. Step 5: Solve for x
    x = 301,776.15/639.47
  6. Step 6: Final answer
    x = 471.92

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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.