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Finding the Fourth Proportional to 458.50, 687.21 and 198.39

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Solution

The fourth proportional to 458.50, 687.21 and 198.39 is: 297.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    458.50 : 687.21 = 198.39 : x
  2. Step 2: Convert to fraction form
    458.50/687.21 = 198.39/x
  3. Step 3: Cross multiply
    458.50x = 687.21 × 198.39
  4. Step 4: Simplify right side
    458.50x = 136,335.59
  5. Step 5: Solve for x
    x = 136,335.59/458.50
  6. Step 6: Final answer
    x = 297.35

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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.