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Finding the Fourth Proportional to 645.54, 968.38 and 212.74

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Solution

The fourth proportional to 645.54, 968.38 and 212.74 is: 319.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.54 : 968.38 = 212.74 : x
  2. Step 2: Convert to fraction form
    645.54/968.38 = 212.74/x
  3. Step 3: Cross multiply
    645.54x = 968.38 × 212.74
  4. Step 4: Simplify right side
    645.54x = 206,013.16
  5. Step 5: Solve for x
    x = 206,013.16/645.54
  6. Step 6: Final answer
    x = 319.13

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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.