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Finding the Fourth Proportional to 399.20, 598.81 and 121.58

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Solution

The fourth proportional to 399.20, 598.81 and 121.58 is: 182.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.20 : 598.81 = 121.58 : x
  2. Step 2: Convert to fraction form
    399.20/598.81 = 121.58/x
  3. Step 3: Cross multiply
    399.20x = 598.81 × 121.58
  4. Step 4: Simplify right side
    399.20x = 72,800.30
  5. Step 5: Solve for x
    x = 72,800.30/399.20
  6. Step 6: Final answer
    x = 182.36

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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.