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Finding the Fourth Proportional to 645.57, 968.09 and 212.76

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Solution

The fourth proportional to 645.57, 968.09 and 212.76 is: 319.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.57 : 968.09 = 212.76 : x
  2. Step 2: Convert to fraction form
    645.57/968.09 = 212.76/x
  3. Step 3: Cross multiply
    645.57x = 968.09 × 212.76
  4. Step 4: Simplify right side
    645.57x = 205,969.76
  5. Step 5: Solve for x
    x = 205,969.76/645.57
  6. Step 6: Final answer
    x = 319.05

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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.