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Finding the Fourth Proportional to 21.01, 28.99 and 18.69

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Solution

The fourth proportional to 21.01, 28.99 and 18.69 is: 25.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.01 : 28.99 = 18.69 : x
  2. Step 2: Convert to fraction form
    21.01/28.99 = 18.69/x
  3. Step 3: Cross multiply
    21.01x = 28.99 × 18.69
  4. Step 4: Simplify right side
    21.01x = 541.82
  5. Step 5: Solve for x
    x = 541.82/21.01
  6. Step 6: Final answer
    x = 25.79

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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.