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Finding the Fourth Proportional to 72.70, 109.11 and 56.77

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Solution

The fourth proportional to 72.70, 109.11 and 56.77 is: 85.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.70 : 109.11 = 56.77 : x
  2. Step 2: Convert to fraction form
    72.70/109.11 = 56.77/x
  3. Step 3: Cross multiply
    72.70x = 109.11 × 56.77
  4. Step 4: Simplify right side
    72.70x = 6,194.17
  5. Step 5: Solve for x
    x = 6,194.17/72.70
  6. Step 6: Final answer
    x = 85.20

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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.