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Finding the Fourth Proportional to 648.31, 972.64 and 215.47

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Solution

The fourth proportional to 648.31, 972.64 and 215.47 is: 323.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.31 : 972.64 = 215.47 : x
  2. Step 2: Convert to fraction form
    648.31/972.64 = 215.47/x
  3. Step 3: Cross multiply
    648.31x = 972.64 × 215.47
  4. Step 4: Simplify right side
    648.31x = 209,574.74
  5. Step 5: Solve for x
    x = 209,574.74/648.31
  6. Step 6: Final answer
    x = 323.26

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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.