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Finding the Fourth Proportional to 258.37, 388.64 and 215.17

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Solution

The fourth proportional to 258.37, 388.64 and 215.17 is: 323.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.37 : 388.64 = 215.17 : x
  2. Step 2: Convert to fraction form
    258.37/388.64 = 215.17/x
  3. Step 3: Cross multiply
    258.37x = 388.64 × 215.17
  4. Step 4: Simplify right side
    258.37x = 83,622.59
  5. Step 5: Solve for x
    x = 83,622.59/258.37
  6. Step 6: Final answer
    x = 323.65

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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.