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Finding the Fourth Proportional to 645.47, 968.20 and 212.66

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Solution

The fourth proportional to 645.47, 968.20 and 212.66 is: 318.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.47 : 968.20 = 212.66 : x
  2. Step 2: Convert to fraction form
    645.47/968.20 = 212.66/x
  3. Step 3: Cross multiply
    645.47x = 968.20 × 212.66
  4. Step 4: Simplify right side
    645.47x = 205,896.87
  5. Step 5: Solve for x
    x = 205,896.87/645.47
  6. Step 6: Final answer
    x = 318.99

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Similar ratio
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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.