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Finding the Fourth Proportional to 258.36, 356.18 and 218.86

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Solution

The fourth proportional to 258.36, 356.18 and 218.86 is: 301.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.36 : 356.18 = 218.86 : x
  2. Step 2: Convert to fraction form
    258.36/356.18 = 218.86/x
  3. Step 3: Cross multiply
    258.36x = 356.18 × 218.86
  4. Step 4: Simplify right side
    258.36x = 77,952.46
  5. Step 5: Solve for x
    x = 77,952.46/258.36
  6. Step 6: Final answer
    x = 301.72

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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.