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Finding the Fourth Proportional to 21.23, 31.80 and 16.71

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Solution

The fourth proportional to 21.23, 31.80 and 16.71 is: 25.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.23 : 31.80 = 16.71 : x
  2. Step 2: Convert to fraction form
    21.23/31.80 = 16.71/x
  3. Step 3: Cross multiply
    21.23x = 31.80 × 16.71
  4. Step 4: Simplify right side
    21.23x = 531.38
  5. Step 5: Solve for x
    x = 531.38/21.23
  6. Step 6: Final answer
    x = 25.04

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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.