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Finding the Fourth Proportional to 284.11, 394.84 and 280.80

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Solution

The fourth proportional to 284.11, 394.84 and 280.80 is: 390.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.11 : 394.84 = 280.80 : x
  2. Step 2: Convert to fraction form
    284.11/394.84 = 280.80/x
  3. Step 3: Cross multiply
    284.11x = 394.84 × 280.80
  4. Step 4: Simplify right side
    284.11x = 110,871.42
  5. Step 5: Solve for x
    x = 110,871.42/284.11
  6. Step 6: Final answer
    x = 390.24

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.