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Finding the Fourth Proportional to 648.06, 972.15 and 209.20

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Solution

The fourth proportional to 648.06, 972.15 and 209.20 is: 313.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.06 : 972.15 = 209.20 : x
  2. Step 2: Convert to fraction form
    648.06/972.15 = 209.20/x
  3. Step 3: Cross multiply
    648.06x = 972.15 × 209.20
  4. Step 4: Simplify right side
    648.06x = 203,367.87
  5. Step 5: Solve for x
    x = 203,367.87/648.06
  6. Step 6: Final answer
    x = 313.81

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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.