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Finding the Fourth Proportional to 5.40, 8.10 and 1.39

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Solution

The fourth proportional to 5.40, 8.10 and 1.39 is: 2.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.40 : 8.10 = 1.39 : x
  2. Step 2: Convert to fraction form
    5.40/8.10 = 1.39/x
  3. Step 3: Cross multiply
    5.40x = 8.10 × 1.39
  4. Step 4: Simplify right side
    5.40x = 11.27
  5. Step 5: Solve for x
    x = 11.27/5.40
  6. Step 6: Final answer
    x = 2.09

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.