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Finding the Fourth Proportional to 311.65, 430.11 and 180.70

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Solution

The fourth proportional to 311.65, 430.11 and 180.70 is: 249.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.65 : 430.11 = 180.70 : x
  2. Step 2: Convert to fraction form
    311.65/430.11 = 180.70/x
  3. Step 3: Cross multiply
    311.65x = 430.11 × 180.70
  4. Step 4: Simplify right side
    311.65x = 77,719.80
  5. Step 5: Solve for x
    x = 77,719.80/311.65
  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.