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Finding the Fourth Proportional to 21.08, 29.07 and 19.15

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Solution

The fourth proportional to 21.08, 29.07 and 19.15 is: 26.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.08 : 29.07 = 19.15 : x
  2. Step 2: Convert to fraction form
    21.08/29.07 = 19.15/x
  3. Step 3: Cross multiply
    21.08x = 29.07 × 19.15
  4. Step 4: Simplify right side
    21.08x = 556.69
  5. Step 5: Solve for x
    x = 556.69/21.08
  6. Step 6: Final answer
    x = 26.41

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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.