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Finding the Fourth Proportional to 21.90, 30.19 and 19.59

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Solution

The fourth proportional to 21.90, 30.19 and 19.59 is: 27.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.90 : 30.19 = 19.59 : x
  2. Step 2: Convert to fraction form
    21.90/30.19 = 19.59/x
  3. Step 3: Cross multiply
    21.90x = 30.19 × 19.59
  4. Step 4: Simplify right side
    21.90x = 591.42
  5. Step 5: Solve for x
    x = 591.42/21.90
  6. Step 6: Final answer
    x = 27.01

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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.