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Finding the Fourth Proportional to 638.87, 958.71 and 407.93

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Solution

The fourth proportional to 638.87, 958.71 and 407.93 is: 612.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.87 : 958.71 = 407.93 : x
  2. Step 2: Convert to fraction form
    638.87/958.71 = 407.93/x
  3. Step 3: Cross multiply
    638.87x = 958.71 × 407.93
  4. Step 4: Simplify right side
    638.87x = 391,081.78
  5. Step 5: Solve for x
    x = 391,081.78/638.87
  6. Step 6: Final answer
    x = 612.15

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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.