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Finding the Fourth Proportional to 499.25, 688.91 and 289.40

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Solution

The fourth proportional to 499.25, 688.91 and 289.40 is: 399.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.25 : 688.91 = 289.40 : x
  2. Step 2: Convert to fraction form
    499.25/688.91 = 289.40/x
  3. Step 3: Cross multiply
    499.25x = 688.91 × 289.40
  4. Step 4: Simplify right side
    499.25x = 199,365.66
  5. Step 5: Solve for x
    x = 199,365.66/499.25
  6. Step 6: Final answer
    x = 399.33

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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.