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Finding the Fourth Proportional to 398.90, 598.31 and 106.39

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Solution

The fourth proportional to 398.90, 598.31 and 106.39 is: 159.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.90 : 598.31 = 106.39 : x
  2. Step 2: Convert to fraction form
    398.90/598.31 = 106.39/x
  3. Step 3: Cross multiply
    398.90x = 598.31 × 106.39
  4. Step 4: Simplify right side
    398.90x = 63,651.21
  5. Step 5: Solve for x
    x = 63,651.21/398.90
  6. Step 6: Final answer
    x = 159.57

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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.