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Finding the Fourth Proportional to 499.40, 688.99 and 289.56

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Solution

The fourth proportional to 499.40, 688.99 and 289.56 is: 399.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.40 : 688.99 = 289.56 : x
  2. Step 2: Convert to fraction form
    499.40/688.99 = 289.56/x
  3. Step 3: Cross multiply
    499.40x = 688.99 × 289.56
  4. Step 4: Simplify right side
    499.40x = 199,503.94
  5. Step 5: Solve for x
    x = 199,503.94/499.40
  6. Step 6: Final answer
    x = 399.49

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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.