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Finding the Fourth Proportional to 500.80, 691.15 and 291

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Solution

The fourth proportional to 500.80, 691.15 and 291 is: 401.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.80 : 691.15 = 291 : x
  2. Step 2: Convert to fraction form
    500.80/691.15 = 291/x
  3. Step 3: Cross multiply
    500.80x = 691.15 × 291
  4. Step 4: Simplify right side
    500.80x = 201,124.65
  5. Step 5: Solve for x
    x = 201,124.65/500.80
  6. Step 6: Final answer
    x = 401.61

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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.