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Finding the Fourth Proportional to 342.59, 513.90 and 86.09

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Solution

The fourth proportional to 342.59, 513.90 and 86.09 is: 129.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.59 : 513.90 = 86.09 : x
  2. Step 2: Convert to fraction form
    342.59/513.90 = 86.09/x
  3. Step 3: Cross multiply
    342.59x = 513.90 × 86.09
  4. Step 4: Simplify right side
    342.59x = 44,241.65
  5. Step 5: Solve for x
    x = 44,241.65/342.59
  6. Step 6: Final answer
    x = 129.14

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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.