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Finding the Fourth Proportional to 258.41, 355.78 and 209.45

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Solution

The fourth proportional to 258.41, 355.78 and 209.45 is: 288.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.41 : 355.78 = 209.45 : x
  2. Step 2: Convert to fraction form
    258.41/355.78 = 209.45/x
  3. Step 3: Cross multiply
    258.41x = 355.78 × 209.45
  4. Step 4: Simplify right side
    258.41x = 74,518.12
  5. Step 5: Solve for x
    x = 74,518.12/258.41
  6. Step 6: Final answer
    x = 288.37

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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.