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Finding the Fourth Proportional to 654.85, 981.98 and 221.90

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Solution

The fourth proportional to 654.85, 981.98 and 221.90 is: 332.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.85 : 981.98 = 221.90 : x
  2. Step 2: Convert to fraction form
    654.85/981.98 = 221.90/x
  3. Step 3: Cross multiply
    654.85x = 981.98 × 221.90
  4. Step 4: Simplify right side
    654.85x = 217,900.25
  5. Step 5: Solve for x
    x = 217,900.25/654.85
  6. Step 6: Final answer
    x = 332.75

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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.