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Finding the Fourth Proportional to 288.20, 398.05 and 190.40

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Solution

The fourth proportional to 288.20, 398.05 and 190.40 is: 262.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.20 : 398.05 = 190.40 : x
  2. Step 2: Convert to fraction form
    288.20/398.05 = 190.40/x
  3. Step 3: Cross multiply
    288.20x = 398.05 × 190.40
  4. Step 4: Simplify right side
    288.20x = 75,786.25
  5. Step 5: Solve for x
    x = 75,786.25/288.20
  6. Step 6: Final answer
    x = 262.96

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.