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Finding the Fourth Proportional to 226.30, 312.28 and 128.05

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Solution

The fourth proportional to 226.30, 312.28 and 128.05 is: 176.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    226.30 : 312.28 = 128.05 : x
  2. Step 2: Convert to fraction form
    226.30/312.28 = 128.05/x
  3. Step 3: Cross multiply
    226.30x = 312.28 × 128.05
  4. Step 4: Simplify right side
    226.30x = 39,987.45
  5. Step 5: Solve for x
    x = 39,987.45/226.30
  6. Step 6: Final answer
    x = 176.70

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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.