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Finding the Fourth Proportional to 253.70, 380.31 and 145.28

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Solution

The fourth proportional to 253.70, 380.31 and 145.28 is: 217.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.70 : 380.31 = 145.28 : x
  2. Step 2: Convert to fraction form
    253.70/380.31 = 145.28/x
  3. Step 3: Cross multiply
    253.70x = 380.31 × 145.28
  4. Step 4: Simplify right side
    253.70x = 55,251.44
  5. Step 5: Solve for x
    x = 55,251.44/253.70
  6. Step 6: Final answer
    x = 217.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.