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Finding the Fourth Proportional to 505.07, 757.50 and 139.87

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Solution

The fourth proportional to 505.07, 757.50 and 139.87 is: 209.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.07 : 757.50 = 139.87 : x
  2. Step 2: Convert to fraction form
    505.07/757.50 = 139.87/x
  3. Step 3: Cross multiply
    505.07x = 757.50 × 139.87
  4. Step 4: Simplify right side
    505.07x = 105,951.53
  5. Step 5: Solve for x
    x = 105,951.53/505.07
  6. Step 6: Final answer
    x = 209.78

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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.