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Finding the Fourth Proportional to 380.28, 570.38 and 136.80

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Solution

The fourth proportional to 380.28, 570.38 and 136.80 is: 205.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.28 : 570.38 = 136.80 : x
  2. Step 2: Convert to fraction form
    380.28/570.38 = 136.80/x
  3. Step 3: Cross multiply
    380.28x = 570.38 × 136.80
  4. Step 4: Simplify right side
    380.28x = 78,027.98
  5. Step 5: Solve for x
    x = 78,027.98/380.28
  6. Step 6: Final answer
    x = 205.19

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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.