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Finding the Fourth Proportional to 398.78, 598.35 and 215.96

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Solution

The fourth proportional to 398.78, 598.35 and 215.96 is: 324.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.78 : 598.35 = 215.96 : x
  2. Step 2: Convert to fraction form
    398.78/598.35 = 215.96/x
  3. Step 3: Cross multiply
    398.78x = 598.35 × 215.96
  4. Step 4: Simplify right side
    398.78x = 129,218.59
  5. Step 5: Solve for x
    x = 129,218.59/398.78
  6. Step 6: Final answer
    x = 324.03

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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.