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Finding the Fourth Proportional to 21.90, 30.18 and 19.02

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Solution

The fourth proportional to 21.90, 30.18 and 19.02 is: 26.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.90 : 30.18 = 19.02 : x
  2. Step 2: Convert to fraction form
    21.90/30.18 = 19.02/x
  3. Step 3: Cross multiply
    21.90x = 30.18 × 19.02
  4. Step 4: Simplify right side
    21.90x = 574.02
  5. Step 5: Solve for x
    x = 574.02/21.90
  6. Step 6: Final answer
    x = 26.21

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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.