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Finding the Fourth Proportional to 171.81, 257.37 and 90.45

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Solution

The fourth proportional to 171.81, 257.37 and 90.45 is: 135.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.81 : 257.37 = 90.45 : x
  2. Step 2: Convert to fraction form
    171.81/257.37 = 90.45/x
  3. Step 3: Cross multiply
    171.81x = 257.37 × 90.45
  4. Step 4: Simplify right side
    171.81x = 23,279.12
  5. Step 5: Solve for x
    x = 23,279.12/171.81
  6. Step 6: Final answer
    x = 135.49

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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.