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Finding the Fourth Proportional to 140.39, 210.26 and 86.12

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Solution

The fourth proportional to 140.39, 210.26 and 86.12 is: 128.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    140.39 : 210.26 = 86.12 : x
  2. Step 2: Convert to fraction form
    140.39/210.26 = 86.12/x
  3. Step 3: Cross multiply
    140.39x = 210.26 × 86.12
  4. Step 4: Simplify right side
    140.39x = 18,106.11
  5. Step 5: Solve for x
    x = 18,106.11/140.39
  6. Step 6: Final answer
    x = 128.97

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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.