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Finding the Fourth Proportional to 399.29, 599.02 and 139.31

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Solution

The fourth proportional to 399.29, 599.02 and 139.31 is: 208.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.29 : 599.02 = 139.31 : x
  2. Step 2: Convert to fraction form
    399.29/599.02 = 139.31/x
  3. Step 3: Cross multiply
    399.29x = 599.02 × 139.31
  4. Step 4: Simplify right side
    399.29x = 83,446.13
  5. Step 5: Solve for x
    x = 83,446.13/399.29
  6. Step 6: Final answer
    x = 208.98

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.