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Finding the Fourth Proportional to 253.85, 380.30 and 145.31

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Solution

The fourth proportional to 253.85, 380.30 and 145.31 is: 217.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.85 : 380.30 = 145.31 : x
  2. Step 2: Convert to fraction form
    253.85/380.30 = 145.31/x
  3. Step 3: Cross multiply
    253.85x = 380.30 × 145.31
  4. Step 4: Simplify right side
    253.85x = 55,261.39
  5. Step 5: Solve for x
    x = 55,261.39/253.85
  6. Step 6: Final answer
    x = 217.69

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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.