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Finding the Fourth Proportional to 648.50, 971.30 and 540.78

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Solution

The fourth proportional to 648.50, 971.30 and 540.78 is: 809.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.50 : 971.30 = 540.78 : x
  2. Step 2: Convert to fraction form
    648.50/971.30 = 540.78/x
  3. Step 3: Cross multiply
    648.50x = 971.30 × 540.78
  4. Step 4: Simplify right side
    648.50x = 525,259.61
  5. Step 5: Solve for x
    x = 525,259.61/648.50
  6. Step 6: Final answer
    x = 809.96

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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.