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Finding the Fourth Proportional to 18.75, 25.81 and 13.89

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Solution

The fourth proportional to 18.75, 25.81 and 13.89 is: 19.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.75 : 25.81 = 13.89 : x
  2. Step 2: Convert to fraction form
    18.75/25.81 = 13.89/x
  3. Step 3: Cross multiply
    18.75x = 25.81 × 13.89
  4. Step 4: Simplify right side
    18.75x = 358.50
  5. Step 5: Solve for x
    x = 358.50/18.75
  6. Step 6: Final answer
    x = 19.12

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Find fourth proportional to 9.38, 12.91 and 6.95
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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.