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Finding the Fourth Proportional to 499.97, 689.78 and 287.31

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Solution

The fourth proportional to 499.97, 689.78 and 287.31 is: 396.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.97 : 689.78 = 287.31 : x
  2. Step 2: Convert to fraction form
    499.97/689.78 = 287.31/x
  3. Step 3: Cross multiply
    499.97x = 689.78 × 287.31
  4. Step 4: Simplify right side
    499.97x = 198,184.00
  5. Step 5: Solve for x
    x = 198,184.00/499.97
  6. Step 6: Final answer
    x = 396.39

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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.