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Finding the Fourth Proportional to 388.25, 581.63 and 257.86

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Solution

The fourth proportional to 388.25, 581.63 and 257.86 is: 386.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.25 : 581.63 = 257.86 : x
  2. Step 2: Convert to fraction form
    388.25/581.63 = 257.86/x
  3. Step 3: Cross multiply
    388.25x = 581.63 × 257.86
  4. Step 4: Simplify right side
    388.25x = 149,977.34
  5. Step 5: Solve for x
    x = 149,977.34/388.25
  6. Step 6: Final answer
    x = 386.29

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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.