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Finding the Fourth Proportional to 258.77, 388.49 and 218.49

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Solution

The fourth proportional to 258.77, 388.49 and 218.49 is: 328.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.77 : 388.49 = 218.49 : x
  2. Step 2: Convert to fraction form
    258.77/388.49 = 218.49/x
  3. Step 3: Cross multiply
    258.77x = 388.49 × 218.49
  4. Step 4: Simplify right side
    258.77x = 84,880.09
  5. Step 5: Solve for x
    x = 84,880.09/258.77
  6. Step 6: Final answer
    x = 328.02

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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.