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Finding the Fourth Proportional to 115.80, 173.30 and 85.29

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Solution

The fourth proportional to 115.80, 173.30 and 85.29 is: 127.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    115.80 : 173.30 = 85.29 : x
  2. Step 2: Convert to fraction form
    115.80/173.30 = 85.29/x
  3. Step 3: Cross multiply
    115.80x = 173.30 × 85.29
  4. Step 4: Simplify right side
    115.80x = 14,780.33
  5. Step 5: Solve for x
    x = 14,780.33/115.80
  6. Step 6: Final answer
    x = 127.64

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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.