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Finding the Fourth Proportional to 505.08, 757.61 and 139.86

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Solution

The fourth proportional to 505.08, 757.61 and 139.86 is: 209.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.08 : 757.61 = 139.86 : x
  2. Step 2: Convert to fraction form
    505.08/757.61 = 139.86/x
  3. Step 3: Cross multiply
    505.08x = 757.61 × 139.86
  4. Step 4: Simplify right side
    505.08x = 105,958.64
  5. Step 5: Solve for x
    x = 105,958.64/505.08
  6. Step 6: Final answer
    x = 209.79

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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.