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Finding the Fourth Proportional to 380.20, 513.75 and 380.20

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Solution

The fourth proportional to 380.20, 513.75 and 380.20 is: 513.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.20 : 513.75 = 380.20 : x
  2. Step 2: Convert to fraction form
    380.20/513.75 = 380.20/x
  3. Step 3: Cross multiply
    380.20x = 513.75 × 380.20
  4. Step 4: Simplify right side
    380.20x = 195,327.75
  5. Step 5: Solve for x
    x = 195,327.75/380.20
  6. Step 6: Final answer
    x = 513.75

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.