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Finding the Fourth Proportional to 648.29, 972.29 and 318.89

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Solution

The fourth proportional to 648.29, 972.29 and 318.89 is: 478.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.29 : 972.29 = 318.89 : x
  2. Step 2: Convert to fraction form
    648.29/972.29 = 318.89/x
  3. Step 3: Cross multiply
    648.29x = 972.29 × 318.89
  4. Step 4: Simplify right side
    648.29x = 310,056.79
  5. Step 5: Solve for x
    x = 310,056.79/648.29
  6. Step 6: Final answer
    x = 478.27

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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.