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Finding the Fourth Proportional to 388.20, 581.39 and 300.72

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Solution

The fourth proportional to 388.20, 581.39 and 300.72 is: 450.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.20 : 581.39 = 300.72 : x
  2. Step 2: Convert to fraction form
    388.20/581.39 = 300.72/x
  3. Step 3: Cross multiply
    388.20x = 581.39 × 300.72
  4. Step 4: Simplify right side
    388.20x = 174,835.60
  5. Step 5: Solve for x
    x = 174,835.60/388.20
  6. Step 6: Final answer
    x = 450.38

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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.