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Finding the Fourth Proportional to 131.80, 197.58 and 76.90

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Solution

The fourth proportional to 131.80, 197.58 and 76.90 is: 115.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.80 : 197.58 = 76.90 : x
  2. Step 2: Convert to fraction form
    131.80/197.58 = 76.90/x
  3. Step 3: Cross multiply
    131.80x = 197.58 × 76.90
  4. Step 4: Simplify right side
    131.80x = 15,193.90
  5. Step 5: Solve for x
    x = 15,193.90/131.80
  6. Step 6: Final answer
    x = 115.28

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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.