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Finding the Fourth Proportional to 20.90, 31.28 and 17.52

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Solution

The fourth proportional to 20.90, 31.28 and 17.52 is: 26.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.90 : 31.28 = 17.52 : x
  2. Step 2: Convert to fraction form
    20.90/31.28 = 17.52/x
  3. Step 3: Cross multiply
    20.90x = 31.28 × 17.52
  4. Step 4: Simplify right side
    20.90x = 547.94
  5. Step 5: Solve for x
    x = 547.94/20.90
  6. Step 6: Final answer
    x = 26.22

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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.