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Finding the Fourth Proportional to 388.20, 536.04 and 257.79

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Solution

The fourth proportional to 388.20, 536.04 and 257.79 is: 355.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.20 : 536.04 = 257.79 : x
  2. Step 2: Convert to fraction form
    388.20/536.04 = 257.79/x
  3. Step 3: Cross multiply
    388.20x = 536.04 × 257.79
  4. Step 4: Simplify right side
    388.20x = 138,185.75
  5. Step 5: Solve for x
    x = 138,185.75/388.20
  6. Step 6: Final answer
    x = 355.97

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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.