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Finding the Fourth Proportional to 72.87, 109.05 and 55.65

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Solution

The fourth proportional to 72.87, 109.05 and 55.65 is: 83.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.87 : 109.05 = 55.65 : x
  2. Step 2: Convert to fraction form
    72.87/109.05 = 55.65/x
  3. Step 3: Cross multiply
    72.87x = 109.05 × 55.65
  4. Step 4: Simplify right side
    72.87x = 6,068.63
  5. Step 5: Solve for x
    x = 6,068.63/72.87
  6. Step 6: Final answer
    x = 83.28

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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.