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Finding the Fourth Proportional to 505.80, 758.07 and 389.79

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Solution

The fourth proportional to 505.80, 758.07 and 389.79 is: 584.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.80 : 758.07 = 389.79 : x
  2. Step 2: Convert to fraction form
    505.80/758.07 = 389.79/x
  3. Step 3: Cross multiply
    505.80x = 758.07 × 389.79
  4. Step 4: Simplify right side
    505.80x = 295,488.11
  5. Step 5: Solve for x
    x = 295,488.11/505.80
  6. Step 6: Final answer
    x = 584.20

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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.