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Finding the Fourth Proportional to 388.85, 535.73 and 318.92

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Solution

The fourth proportional to 388.85, 535.73 and 318.92 is: 439.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.85 : 535.73 = 318.92 : x
  2. Step 2: Convert to fraction form
    388.85/535.73 = 318.92/x
  3. Step 3: Cross multiply
    388.85x = 535.73 × 318.92
  4. Step 4: Simplify right side
    388.85x = 170,850.74
  5. Step 5: Solve for x
    x = 170,850.74/388.85
  6. Step 6: Final answer
    x = 439.38

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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.