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Finding the Fourth Proportional to 654.70, 981.78 and 221.80

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Solution

The fourth proportional to 654.70, 981.78 and 221.80 is: 332.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.70 : 981.78 = 221.80 : x
  2. Step 2: Convert to fraction form
    654.70/981.78 = 221.80/x
  3. Step 3: Cross multiply
    654.70x = 981.78 × 221.80
  4. Step 4: Simplify right side
    654.70x = 217,758.80
  5. Step 5: Solve for x
    x = 217,758.80/654.70
  6. Step 6: Final answer
    x = 332.61

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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.