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Finding the Fourth Proportional to 648.20, 972.02 and 215.16

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Solution

The fourth proportional to 648.20, 972.02 and 215.16 is: 322.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.20 : 972.02 = 215.16 : x
  2. Step 2: Convert to fraction form
    648.20/972.02 = 215.16/x
  3. Step 3: Cross multiply
    648.20x = 972.02 × 215.16
  4. Step 4: Simplify right side
    648.20x = 209,139.82
  5. Step 5: Solve for x
    x = 209,139.82/648.20
  6. Step 6: Final answer
    x = 322.65

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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.