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Finding the Fourth Proportional to 72.45, 108.50 and 55.31

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Solution

The fourth proportional to 72.45, 108.50 and 55.31 is: 82.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.45 : 108.50 = 55.31 : x
  2. Step 2: Convert to fraction form
    72.45/108.50 = 55.31/x
  3. Step 3: Cross multiply
    72.45x = 108.50 × 55.31
  4. Step 4: Simplify right side
    72.45x = 6,000.32
  5. Step 5: Solve for x
    x = 6,000.32/72.45
  6. Step 6: Final answer
    x = 82.82

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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.