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Finding the Fourth Proportional to 131.55, 197.15 and 90.65

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Solution

The fourth proportional to 131.55, 197.15 and 90.65 is: 135.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.55 : 197.15 = 90.65 : x
  2. Step 2: Convert to fraction form
    131.55/197.15 = 90.65/x
  3. Step 3: Cross multiply
    131.55x = 197.15 × 90.65
  4. Step 4: Simplify right side
    131.55x = 17,871.65
  5. Step 5: Solve for x
    x = 17,871.65/131.55
  6. Step 6: Final answer
    x = 135.85

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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.