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Finding the Fourth Proportional to 387.45, 534.60 and 256.41

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Solution

The fourth proportional to 387.45, 534.60 and 256.41 is: 353.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.45 : 534.60 = 256.41 : x
  2. Step 2: Convert to fraction form
    387.45/534.60 = 256.41/x
  3. Step 3: Cross multiply
    387.45x = 534.60 × 256.41
  4. Step 4: Simplify right side
    387.45x = 137,076.79
  5. Step 5: Solve for x
    x = 137,076.79/387.45
  6. Step 6: Final answer
    x = 353.79

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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.