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Finding the Fourth Proportional to 207.31, 285.78 and 145.15

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Solution

The fourth proportional to 207.31, 285.78 and 145.15 is: 200.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.31 : 285.78 = 145.15 : x
  2. Step 2: Convert to fraction form
    207.31/285.78 = 145.15/x
  3. Step 3: Cross multiply
    207.31x = 285.78 × 145.15
  4. Step 4: Simplify right side
    207.31x = 41,480.97
  5. Step 5: Solve for x
    x = 41,480.97/207.31
  6. Step 6: Final answer
    x = 200.09

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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.