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Finding the Fourth Proportional to 287.86, 397.20 and 171.45

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Solution

The fourth proportional to 287.86, 397.20 and 171.45 is: 236.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.86 : 397.20 = 171.45 : x
  2. Step 2: Convert to fraction form
    287.86/397.20 = 171.45/x
  3. Step 3: Cross multiply
    287.86x = 397.20 × 171.45
  4. Step 4: Simplify right side
    287.86x = 68,099.94
  5. Step 5: Solve for x
    x = 68,099.94/287.86
  6. Step 6: Final answer
    x = 236.57

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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.