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Finding the Fourth Proportional to 130.28, 178.62 and 128.16

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Solution

The fourth proportional to 130.28, 178.62 and 128.16 is: 175.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.28 : 178.62 = 128.16 : x
  2. Step 2: Convert to fraction form
    130.28/178.62 = 128.16/x
  3. Step 3: Cross multiply
    130.28x = 178.62 × 128.16
  4. Step 4: Simplify right side
    130.28x = 22,891.94
  5. Step 5: Solve for x
    x = 22,891.94/130.28
  6. Step 6: Final answer
    x = 175.71

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.