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Finding the Fourth Proportional to 807.78, 1,208.70 and 499.80

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Solution

The fourth proportional to 807.78, 1,208.70 and 499.80 is: 747.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.78 : 1,208.70 = 499.80 : x
  2. Step 2: Convert to fraction form
    807.78/1,208.70 = 499.80/x
  3. Step 3: Cross multiply
    807.78x = 1,208.70 × 499.80
  4. Step 4: Simplify right side
    807.78x = 604,108.26
  5. Step 5: Solve for x
    x = 604,108.26/807.78
  6. Step 6: Final answer
    x = 747.86

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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.