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Finding the Fourth Proportional to 648.30, 971.85 and 215.16

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Solution

The fourth proportional to 648.30, 971.85 and 215.16 is: 322.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.30 : 971.85 = 215.16 : x
  2. Step 2: Convert to fraction form
    648.30/971.85 = 215.16/x
  3. Step 3: Cross multiply
    648.30x = 971.85 × 215.16
  4. Step 4: Simplify right side
    648.30x = 209,099.20
  5. Step 5: Solve for x
    x = 209,099.20/648.30
  6. Step 6: Final answer
    x = 322.53

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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.