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Finding the Fourth Proportional to 78.80, 118.01 and 67.29

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Solution

The fourth proportional to 78.80, 118.01 and 67.29 is: 100.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.80 : 118.01 = 67.29 : x
  2. Step 2: Convert to fraction form
    78.80/118.01 = 67.29/x
  3. Step 3: Cross multiply
    78.80x = 118.01 × 67.29
  4. Step 4: Simplify right side
    78.80x = 7,940.56
  5. Step 5: Solve for x
    x = 7,940.56/78.80
  6. Step 6: Final answer
    x = 100.77

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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.