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Finding the Fourth Proportional to 258.64, 387.26 and 155.78

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Solution

The fourth proportional to 258.64, 387.26 and 155.78 is: 233.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.64 : 387.26 = 155.78 : x
  2. Step 2: Convert to fraction form
    258.64/387.26 = 155.78/x
  3. Step 3: Cross multiply
    258.64x = 387.26 × 155.78
  4. Step 4: Simplify right side
    258.64x = 60,328.72
  5. Step 5: Solve for x
    x = 60,328.72/258.64
  6. Step 6: Final answer
    x = 233.26

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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.