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Finding the Fourth Proportional to 311.66, 430.06 and 180.72

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Solution

The fourth proportional to 311.66, 430.06 and 180.72 is: 249.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.66 : 430.06 = 180.72 : x
  2. Step 2: Convert to fraction form
    311.66/430.06 = 180.72/x
  3. Step 3: Cross multiply
    311.66x = 430.06 × 180.72
  4. Step 4: Simplify right side
    311.66x = 77,720.44
  5. Step 5: Solve for x
    x = 77,720.44/311.66
  6. Step 6: Final answer
    x = 249.38

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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.