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Finding the Fourth Proportional to 654.40, 981.68 and 221.68

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Solution

The fourth proportional to 654.40, 981.68 and 221.68 is: 332.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.40 : 981.68 = 221.68 : x
  2. Step 2: Convert to fraction form
    654.40/981.68 = 221.68/x
  3. Step 3: Cross multiply
    654.40x = 981.68 × 221.68
  4. Step 4: Simplify right side
    654.40x = 217,618.82
  5. Step 5: Solve for x
    x = 217,618.82/654.40
  6. Step 6: Final answer
    x = 332.55

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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.