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Finding the Fourth Proportional to 18.40, 25.28 and 17.20

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Solution

The fourth proportional to 18.40, 25.28 and 17.20 is: 23.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.40 : 25.28 = 17.20 : x
  2. Step 2: Convert to fraction form
    18.40/25.28 = 17.20/x
  3. Step 3: Cross multiply
    18.40x = 25.28 × 17.20
  4. Step 4: Simplify right side
    18.40x = 434.82
  5. Step 5: Solve for x
    x = 434.82/18.40
  6. Step 6: Final answer
    x = 23.63

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.