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Finding the Fourth Proportional to 648.80, 971.84 and 511.20

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Solution

The fourth proportional to 648.80, 971.84 and 511.20 is: 765.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.80 : 971.84 = 511.20 : x
  2. Step 2: Convert to fraction form
    648.80/971.84 = 511.20/x
  3. Step 3: Cross multiply
    648.80x = 971.84 × 511.20
  4. Step 4: Simplify right side
    648.80x = 496,804.61
  5. Step 5: Solve for x
    x = 496,804.61/648.80
  6. Step 6: Final answer
    x = 765.73

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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.