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Finding the Fourth Proportional to 72.98, 109.31 and 57.69

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Solution

The fourth proportional to 72.98, 109.31 and 57.69 is: 86.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.98 : 109.31 = 57.69 : x
  2. Step 2: Convert to fraction form
    72.98/109.31 = 57.69/x
  3. Step 3: Cross multiply
    72.98x = 109.31 × 57.69
  4. Step 4: Simplify right side
    72.98x = 6,305.81
  5. Step 5: Solve for x
    x = 6,305.81/72.98
  6. Step 6: Final answer
    x = 86.41

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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.