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Finding the Fourth Proportional to 355.41, 490.46 and 280.80

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Solution

The fourth proportional to 355.41, 490.46 and 280.80 is: 387.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    355.41 : 490.46 = 280.80 : x
  2. Step 2: Convert to fraction form
    355.41/490.46 = 280.80/x
  3. Step 3: Cross multiply
    355.41x = 490.46 × 280.80
  4. Step 4: Simplify right side
    355.41x = 137,719.76
  5. Step 5: Solve for x
    x = 137,719.76/355.41
  6. Step 6: Final answer
    x = 387.50

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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.