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Finding the Fourth Proportional to 499.09, 688.68 and 289.23

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Solution

The fourth proportional to 499.09, 688.68 and 289.23 is: 399.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.09 : 688.68 = 289.23 : x
  2. Step 2: Convert to fraction form
    499.09/688.68 = 289.23/x
  3. Step 3: Cross multiply
    499.09x = 688.68 × 289.23
  4. Step 4: Simplify right side
    499.09x = 199,186.92
  5. Step 5: Solve for x
    x = 199,186.92/499.09
  6. Step 6: Final answer
    x = 399.10

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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.