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Finding the Fourth Proportional to 387.19, 581.20 and 378.49

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Solution

The fourth proportional to 387.19, 581.20 and 378.49 is: 568.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.19 : 581.20 = 378.49 : x
  2. Step 2: Convert to fraction form
    387.19/581.20 = 378.49/x
  3. Step 3: Cross multiply
    387.19x = 581.20 × 378.49
  4. Step 4: Simplify right side
    387.19x = 219,976.50
  5. Step 5: Solve for x
    x = 219,976.50/387.19
  6. Step 6: Final answer
    x = 568.14

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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.