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Finding the Fourth Proportional to 499.09, 688.57 and 289.21

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Solution

The fourth proportional to 499.09, 688.57 and 289.21 is: 399.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.09 : 688.57 = 289.21 : x
  2. Step 2: Convert to fraction form
    499.09/688.57 = 289.21/x
  3. Step 3: Cross multiply
    499.09x = 688.57 × 289.21
  4. Step 4: Simplify right side
    499.09x = 199,141.33
  5. Step 5: Solve for x
    x = 199,141.33/499.09
  6. Step 6: Final answer
    x = 399.01

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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.