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Finding the Fourth Proportional to 171.39, 257.10 and 90.23

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Solution

The fourth proportional to 171.39, 257.10 and 90.23 is: 135.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.39 : 257.10 = 90.23 : x
  2. Step 2: Convert to fraction form
    171.39/257.10 = 90.23/x
  3. Step 3: Cross multiply
    171.39x = 257.10 × 90.23
  4. Step 4: Simplify right side
    171.39x = 23,198.78
  5. Step 5: Solve for x
    x = 23,198.78/171.39
  6. Step 6: Final answer
    x = 135.36

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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.