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Finding the Fourth Proportional to 128.60, 178.22 and 127.10

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Solution

The fourth proportional to 128.60, 178.22 and 127.10 is: 176.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.60 : 178.22 = 127.10 : x
  2. Step 2: Convert to fraction form
    128.60/178.22 = 127.10/x
  3. Step 3: Cross multiply
    128.60x = 178.22 × 127.10
  4. Step 4: Simplify right side
    128.60x = 22,651.76
  5. Step 5: Solve for x
    x = 22,651.76/128.60
  6. Step 6: Final answer
    x = 176.14

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.