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Finding the Fourth Proportional to 387.20, 534.42 and 256.22

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Solution

The fourth proportional to 387.20, 534.42 and 256.22 is: 353.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.20 : 534.42 = 256.22 : x
  2. Step 2: Convert to fraction form
    387.20/534.42 = 256.22/x
  3. Step 3: Cross multiply
    387.20x = 534.42 × 256.22
  4. Step 4: Simplify right side
    387.20x = 136,929.09
  5. Step 5: Solve for x
    x = 136,929.09/387.20
  6. Step 6: Final answer
    x = 353.64

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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.