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Finding the Fourth Proportional to 215.98, 298.02 and 128.65

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Solution

The fourth proportional to 215.98, 298.02 and 128.65 is: 177.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.98 : 298.02 = 128.65 : x
  2. Step 2: Convert to fraction form
    215.98/298.02 = 128.65/x
  3. Step 3: Cross multiply
    215.98x = 298.02 × 128.65
  4. Step 4: Simplify right side
    215.98x = 38,340.27
  5. Step 5: Solve for x
    x = 38,340.27/215.98
  6. Step 6: Final answer
    x = 177.52

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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.