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Finding the Fourth Proportional to 258.52, 387.78 and 87.48

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Solution

The fourth proportional to 258.52, 387.78 and 87.48 is: 131.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.52 : 387.78 = 87.48 : x
  2. Step 2: Convert to fraction form
    258.52/387.78 = 87.48/x
  3. Step 3: Cross multiply
    258.52x = 387.78 × 87.48
  4. Step 4: Simplify right side
    258.52x = 33,922.99
  5. Step 5: Solve for x
    x = 33,922.99/258.52
  6. Step 6: Final answer
    x = 131.22

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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.