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Finding the Fourth Proportional to 287.61, 396.79 and 171.15

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Solution

The fourth proportional to 287.61, 396.79 and 171.15 is: 236.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.61 : 396.79 = 171.15 : x
  2. Step 2: Convert to fraction form
    287.61/396.79 = 171.15/x
  3. Step 3: Cross multiply
    287.61x = 396.79 × 171.15
  4. Step 4: Simplify right side
    287.61x = 67,910.61
  5. Step 5: Solve for x
    x = 67,910.61/287.61
  6. Step 6: Final answer
    x = 236.12

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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.