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Finding the Fourth Proportional to 288.78, 398.38 and 195.56

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Solution

The fourth proportional to 288.78, 398.38 and 195.56 is: 269.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.78 : 398.38 = 195.56 : x
  2. Step 2: Convert to fraction form
    288.78/398.38 = 195.56/x
  3. Step 3: Cross multiply
    288.78x = 398.38 × 195.56
  4. Step 4: Simplify right side
    288.78x = 77,907.19
  5. Step 5: Solve for x
    x = 77,907.19/288.78
  6. Step 6: Final answer
    x = 269.78

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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.