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Finding the Fourth Proportional to 145.89, 219.09 and 138.21

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Solution

The fourth proportional to 145.89, 219.09 and 138.21 is: 207.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.89 : 219.09 = 138.21 : x
  2. Step 2: Convert to fraction form
    145.89/219.09 = 138.21/x
  3. Step 3: Cross multiply
    145.89x = 219.09 × 138.21
  4. Step 4: Simplify right side
    145.89x = 30,280.43
  5. Step 5: Solve for x
    x = 30,280.43/145.89
  6. Step 6: Final answer
    x = 207.56

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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.