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Finding the Fourth Proportional to 500.80, 691.60 and 418.80

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Solution

The fourth proportional to 500.80, 691.60 and 418.80 is: 578.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.80 : 691.60 = 418.80 : x
  2. Step 2: Convert to fraction form
    500.80/691.60 = 418.80/x
  3. Step 3: Cross multiply
    500.80x = 691.60 × 418.80
  4. Step 4: Simplify right side
    500.80x = 289,642.08
  5. Step 5: Solve for x
    x = 289,642.08/500.80
  6. Step 6: Final answer
    x = 578.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.