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Finding the Fourth Proportional to 21.25, 29.27 and 18.31

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Solution

The fourth proportional to 21.25, 29.27 and 18.31 is: 25.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.25 : 29.27 = 18.31 : x
  2. Step 2: Convert to fraction form
    21.25/29.27 = 18.31/x
  3. Step 3: Cross multiply
    21.25x = 29.27 × 18.31
  4. Step 4: Simplify right side
    21.25x = 535.93
  5. Step 5: Solve for x
    x = 535.93/21.25
  6. Step 6: Final answer
    x = 25.22

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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.