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Finding the Fourth Proportional to 388.58, 535.92 and 257.60

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Solution

The fourth proportional to 388.58, 535.92 and 257.60 is: 355.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.58 : 535.92 = 257.60 : x
  2. Step 2: Convert to fraction form
    388.58/535.92 = 257.60/x
  3. Step 3: Cross multiply
    388.58x = 535.92 × 257.60
  4. Step 4: Simplify right side
    388.58x = 138,052.99
  5. Step 5: Solve for x
    x = 138,052.99/388.58
  6. Step 6: Final answer
    x = 355.28

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.