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Finding the Fourth Proportional to 215.95, 298.04 and 128.63

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Solution

The fourth proportional to 215.95, 298.04 and 128.63 is: 177.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.95 : 298.04 = 128.63 : x
  2. Step 2: Convert to fraction form
    215.95/298.04 = 128.63/x
  3. Step 3: Cross multiply
    215.95x = 298.04 × 128.63
  4. Step 4: Simplify right side
    215.95x = 38,335.96
  5. Step 5: Solve for x
    x = 38,335.96/215.95
  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.