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Finding the Fourth Proportional to 15.31, 23 and 15.21

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Solution

The fourth proportional to 15.31, 23 and 15.21 is: 22.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.31 : 23 = 15.21 : x
  2. Step 2: Convert to fraction form
    15.31/23 = 15.21/x
  3. Step 3: Cross multiply
    15.31x = 23 × 15.21
  4. Step 4: Simplify right side
    15.31x = 349.83
  5. Step 5: Solve for x
    x = 349.83/15.31
  6. Step 6: Final answer
    x = 22.85

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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.