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Finding the Fourth Proportional to 654.20, 981.39 and 215.30

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Solution

The fourth proportional to 654.20, 981.39 and 215.30 is: 322.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.20 : 981.39 = 215.30 : x
  2. Step 2: Convert to fraction form
    654.20/981.39 = 215.30/x
  3. Step 3: Cross multiply
    654.20x = 981.39 × 215.30
  4. Step 4: Simplify right side
    654.20x = 211,293.27
  5. Step 5: Solve for x
    x = 211,293.27/654.20
  6. Step 6: Final answer
    x = 322.98

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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.