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Finding the Fourth Proportional to 648.57, 972.99 and 215.72

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Solution

The fourth proportional to 648.57, 972.99 and 215.72 is: 323.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.57 : 972.99 = 215.72 : x
  2. Step 2: Convert to fraction form
    648.57/972.99 = 215.72/x
  3. Step 3: Cross multiply
    648.57x = 972.99 × 215.72
  4. Step 4: Simplify right side
    648.57x = 209,888.54
  5. Step 5: Solve for x
    x = 209,888.54/648.57
  6. Step 6: Final answer
    x = 323.62

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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.