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Finding the Fourth Proportional to 78.87, 118.11 and 72.93

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Solution

The fourth proportional to 78.87, 118.11 and 72.93 is: 109.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.87 : 118.11 = 72.93 : x
  2. Step 2: Convert to fraction form
    78.87/118.11 = 72.93/x
  3. Step 3: Cross multiply
    78.87x = 118.11 × 72.93
  4. Step 4: Simplify right side
    78.87x = 8,613.76
  5. Step 5: Solve for x
    x = 8,613.76/78.87
  6. Step 6: Final answer
    x = 109.21

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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.