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Finding the Fourth Proportional to 127.20, 175.55 and 77.39

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Solution

The fourth proportional to 127.20, 175.55 and 77.39 is: 106.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    127.20 : 175.55 = 77.39 : x
  2. Step 2: Convert to fraction form
    127.20/175.55 = 77.39/x
  3. Step 3: Cross multiply
    127.20x = 175.55 × 77.39
  4. Step 4: Simplify right side
    127.20x = 13,584.55
  5. Step 5: Solve for x
    x = 13,584.55/127.20
  6. Step 6: Final answer
    x = 106.80

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.