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Finding the Fourth Proportional to 2.59, 3.89 and 0.81

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Solution

The fourth proportional to 2.59, 3.89 and 0.81 is: 1.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.59 : 3.89 = 0.81 : x
  2. Step 2: Convert to fraction form
    2.59/3.89 = 0.81/x
  3. Step 3: Cross multiply
    2.59x = 3.89 × 0.81
  4. Step 4: Simplify right side
    2.59x = 3.16
  5. Step 5: Solve for x
    x = 3.16/2.59
  6. Step 6: Final answer
    x = 1.22

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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.