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Finding the Fourth Proportional to 127.10, 190.40 and 86.56

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Solution

The fourth proportional to 127.10, 190.40 and 86.56 is: 129.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    127.10 : 190.40 = 86.56 : x
  2. Step 2: Convert to fraction form
    127.10/190.40 = 86.56/x
  3. Step 3: Cross multiply
    127.10x = 190.40 × 86.56
  4. Step 4: Simplify right side
    127.10x = 16,481.02
  5. Step 5: Solve for x
    x = 16,481.02/127.10
  6. Step 6: Final answer
    x = 129.67

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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.