Home / 21.20-29.28-18.14

Finding the Fourth Proportional to 21.20, 29.28 and 18.14

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Solution

The fourth proportional to 21.20, 29.28 and 18.14 is: 25.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.20 : 29.28 = 18.14 : x
  2. Step 2: Convert to fraction form
    21.20/29.28 = 18.14/x
  3. Step 3: Cross multiply
    21.20x = 29.28 × 18.14
  4. Step 4: Simplify right side
    21.20x = 531.14
  5. Step 5: Solve for x
    x = 531.14/21.20
  6. Step 6: Final answer
    x = 25.05

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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.