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Finding the Fourth Proportional to 311.78, 430.27 and 180.76

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Solution

The fourth proportional to 311.78, 430.27 and 180.76 is: 249.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.78 : 430.27 = 180.76 : x
  2. Step 2: Convert to fraction form
    311.78/430.27 = 180.76/x
  3. Step 3: Cross multiply
    311.78x = 430.27 × 180.76
  4. Step 4: Simplify right side
    311.78x = 77,775.61
  5. Step 5: Solve for x
    x = 77,775.61/311.78
  6. Step 6: Final answer
    x = 249.46

Related Problems

Find fourth proportional to 155.89, 215.14 and 90.38
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Double scale
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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.