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Finding the Fourth Proportional to 638.93, 958.53 and 206.39

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Solution

The fourth proportional to 638.93, 958.53 and 206.39 is: 309.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.93 : 958.53 = 206.39 : x
  2. Step 2: Convert to fraction form
    638.93/958.53 = 206.39/x
  3. Step 3: Cross multiply
    638.93x = 958.53 × 206.39
  4. Step 4: Simplify right side
    638.93x = 197,831.01
  5. Step 5: Solve for x
    x = 197,831.01/638.93
  6. Step 6: Final answer
    x = 309.63

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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.