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Finding the Fourth Proportional to 270.90, 406.23 and 85.75

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Solution

The fourth proportional to 270.90, 406.23 and 85.75 is: 128.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    270.90 : 406.23 = 85.75 : x
  2. Step 2: Convert to fraction form
    270.90/406.23 = 85.75/x
  3. Step 3: Cross multiply
    270.90x = 406.23 × 85.75
  4. Step 4: Simplify right side
    270.90x = 34,834.81
  5. Step 5: Solve for x
    x = 34,834.81/270.90
  6. Step 6: Final answer
    x = 128.59

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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.