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Finding the Fourth Proportional to 387.79, 535.17 and 238.39

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Solution

The fourth proportional to 387.79, 535.17 and 238.39 is: 328.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.79 : 535.17 = 238.39 : x
  2. Step 2: Convert to fraction form
    387.79/535.17 = 238.39/x
  3. Step 3: Cross multiply
    387.79x = 535.17 × 238.39
  4. Step 4: Simplify right side
    387.79x = 127,579.18
  5. Step 5: Solve for x
    x = 127,579.18/387.79
  6. Step 6: Final answer
    x = 328.99

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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.