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Finding the Fourth Proportional to 499.02, 688.62 and 289.21

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Solution

The fourth proportional to 499.02, 688.62 and 289.21 is: 399.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.02 : 688.62 = 289.21 : x
  2. Step 2: Convert to fraction form
    499.02/688.62 = 289.21/x
  3. Step 3: Cross multiply
    499.02x = 688.62 × 289.21
  4. Step 4: Simplify right side
    499.02x = 199,154.46
  5. Step 5: Solve for x
    x = 199,154.46/499.02
  6. Step 6: Final answer
    x = 399.09

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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.