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Finding the Fourth Proportional to 281.78, 388.90 and 171.28

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Solution

The fourth proportional to 281.78, 388.90 and 171.28 is: 236.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.78 : 388.90 = 171.28 : x
  2. Step 2: Convert to fraction form
    281.78/388.90 = 171.28/x
  3. Step 3: Cross multiply
    281.78x = 388.90 × 171.28
  4. Step 4: Simplify right side
    281.78x = 66,610.79
  5. Step 5: Solve for x
    x = 66,610.79/281.78
  6. Step 6: Final answer
    x = 236.39

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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.