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Finding the Fourth Proportional to 505.86, 756.83 and 390.71

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Solution

The fourth proportional to 505.86, 756.83 and 390.71 is: 584.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.86 : 756.83 = 390.71 : x
  2. Step 2: Convert to fraction form
    505.86/756.83 = 390.71/x
  3. Step 3: Cross multiply
    505.86x = 756.83 × 390.71
  4. Step 4: Simplify right side
    505.86x = 295,695.31
  5. Step 5: Solve for x
    x = 295,695.31/505.86
  6. Step 6: Final answer
    x = 584.54

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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.