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Finding the Fourth Proportional to 80.39, 120.36 and 65.00

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Solution

The fourth proportional to 80.39, 120.36 and 65.00 is: 97.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.39 : 120.36 = 65.00 : x
  2. Step 2: Convert to fraction form
    80.39/120.36 = 65.00/x
  3. Step 3: Cross multiply
    80.39x = 120.36 × 65.00
  4. Step 4: Simplify right side
    80.39x = 7,822.80
  5. Step 5: Solve for x
    x = 7,822.80/80.39
  6. Step 6: Final answer
    x = 97.32

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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.