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Finding the Fourth Proportional to 128.58, 177.46 and 107.82

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Solution

The fourth proportional to 128.58, 177.46 and 107.82 is: 148.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.58 : 177.46 = 107.82 : x
  2. Step 2: Convert to fraction form
    128.58/177.46 = 107.82/x
  3. Step 3: Cross multiply
    128.58x = 177.46 × 107.82
  4. Step 4: Simplify right side
    128.58x = 19,133.74
  5. Step 5: Solve for x
    x = 19,133.74/128.58
  6. Step 6: Final answer
    x = 148.81

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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.