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Finding the Fourth Proportional to 80.02, 109.51 and 78.34

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Solution

The fourth proportional to 80.02, 109.51 and 78.34 is: 107.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.02 : 109.51 = 78.34 : x
  2. Step 2: Convert to fraction form
    80.02/109.51 = 78.34/x
  3. Step 3: Cross multiply
    80.02x = 109.51 × 78.34
  4. Step 4: Simplify right side
    80.02x = 8,578.62
  5. Step 5: Solve for x
    x = 8,578.62/80.02
  6. Step 6: Final answer
    x = 107.21

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.