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Finding the Fourth Proportional to 21.09, 31.66 and 10.97

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Solution

The fourth proportional to 21.09, 31.66 and 10.97 is: 16.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.09 : 31.66 = 10.97 : x
  2. Step 2: Convert to fraction form
    21.09/31.66 = 10.97/x
  3. Step 3: Cross multiply
    21.09x = 31.66 × 10.97
  4. Step 4: Simplify right side
    21.09x = 347.24
  5. Step 5: Solve for x
    x = 347.24/21.09
  6. Step 6: Final answer
    x = 16.46

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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.