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Finding the Fourth Proportional to 127.07, 175.20 and 100.78

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Solution

The fourth proportional to 127.07, 175.20 and 100.78 is: 138.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    127.07 : 175.20 = 100.78 : x
  2. Step 2: Convert to fraction form
    127.07/175.20 = 100.78/x
  3. Step 3: Cross multiply
    127.07x = 175.20 × 100.78
  4. Step 4: Simplify right side
    127.07x = 17,655.84
  5. Step 5: Solve for x
    x = 17,655.84/127.07
  6. Step 6: Final answer
    x = 138.95

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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.