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Finding the Fourth Proportional to 280.40, 385.80 and 273.92

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Solution

The fourth proportional to 280.40, 385.80 and 273.92 is: 376.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.40 : 385.80 = 273.92 : x
  2. Step 2: Convert to fraction form
    280.40/385.80 = 273.92/x
  3. Step 3: Cross multiply
    280.40x = 385.80 × 273.92
  4. Step 4: Simplify right side
    280.40x = 105,678.34
  5. Step 5: Solve for x
    x = 105,678.34/280.40
  6. Step 6: Final answer
    x = 376.88

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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.