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Finding the Fourth Proportional to 342.35, 513.53 and 85.85

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Solution

The fourth proportional to 342.35, 513.53 and 85.85 is: 128.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.35 : 513.53 = 85.85 : x
  2. Step 2: Convert to fraction form
    342.35/513.53 = 85.85/x
  3. Step 3: Cross multiply
    342.35x = 513.53 × 85.85
  4. Step 4: Simplify right side
    342.35x = 44,088.05
  5. Step 5: Solve for x
    x = 44,088.05/342.35
  6. Step 6: Final answer
    x = 128.78

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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.