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Finding the Fourth Proportional to 72.56, 108.21 and 69.77

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Solution

The fourth proportional to 72.56, 108.21 and 69.77 is: 104.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.56 : 108.21 = 69.77 : x
  2. Step 2: Convert to fraction form
    72.56/108.21 = 69.77/x
  3. Step 3: Cross multiply
    72.56x = 108.21 × 69.77
  4. Step 4: Simplify right side
    72.56x = 7,549.27
  5. Step 5: Solve for x
    x = 7,549.27/72.56
  6. Step 6: Final answer
    x = 104.05

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.