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Finding the Fourth Proportional to 648.72, 972.72 and 258.48

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Solution

The fourth proportional to 648.72, 972.72 and 258.48 is: 387.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.72 : 972.72 = 258.48 : x
  2. Step 2: Convert to fraction form
    648.72/972.72 = 258.48/x
  3. Step 3: Cross multiply
    648.72x = 972.72 × 258.48
  4. Step 4: Simplify right side
    648.72x = 251,428.67
  5. Step 5: Solve for x
    x = 251,428.67/648.72
  6. Step 6: Final answer
    x = 387.58

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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.