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Finding the Fourth Proportional to 370.82, 511.20 and 311.87

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Solution

The fourth proportional to 370.82, 511.20 and 311.87 is: 429.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    370.82 : 511.20 = 311.87 : x
  2. Step 2: Convert to fraction form
    370.82/511.20 = 311.87/x
  3. Step 3: Cross multiply
    370.82x = 511.20 × 311.87
  4. Step 4: Simplify right side
    370.82x = 159,425.39
  5. Step 5: Solve for x
    x = 159,425.39/370.82
  6. Step 6: Final answer
    x = 429.93

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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.