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Finding the Fourth Proportional to 72.80, 100.14 and 67.40

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Solution

The fourth proportional to 72.80, 100.14 and 67.40 is: 92.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.80 : 100.14 = 67.40 : x
  2. Step 2: Convert to fraction form
    72.80/100.14 = 67.40/x
  3. Step 3: Cross multiply
    72.80x = 100.14 × 67.40
  4. Step 4: Simplify right side
    72.80x = 6,749.44
  5. Step 5: Solve for x
    x = 6,749.44/72.80
  6. Step 6: Final answer
    x = 92.71

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.