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Finding the Fourth Proportional to 342.20, 513.30 and 255.80

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Solution

The fourth proportional to 342.20, 513.30 and 255.80 is: 383.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.20 : 513.30 = 255.80 : x
  2. Step 2: Convert to fraction form
    342.20/513.30 = 255.80/x
  3. Step 3: Cross multiply
    342.20x = 513.30 × 255.80
  4. Step 4: Simplify right side
    342.20x = 131,302.14
  5. Step 5: Solve for x
    x = 131,302.14/342.20
  6. Step 6: Final answer
    x = 383.70

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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.