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Finding the Fourth Proportional to 499.83, 689.85 and 300.78

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Solution

The fourth proportional to 499.83, 689.85 and 300.78 is: 415.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.83 : 689.85 = 300.78 : x
  2. Step 2: Convert to fraction form
    499.83/689.85 = 300.78/x
  3. Step 3: Cross multiply
    499.83x = 689.85 × 300.78
  4. Step 4: Simplify right side
    499.83x = 207,493.08
  5. Step 5: Solve for x
    x = 207,493.08/499.83
  6. Step 6: Final answer
    x = 415.13

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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.