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Finding the Fourth Proportional to 280.42, 422.78 and 254.30

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Solution

The fourth proportional to 280.42, 422.78 and 254.30 is: 383.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.42 : 422.78 = 254.30 : x
  2. Step 2: Convert to fraction form
    280.42/422.78 = 254.30/x
  3. Step 3: Cross multiply
    280.42x = 422.78 × 254.30
  4. Step 4: Simplify right side
    280.42x = 107,512.95
  5. Step 5: Solve for x
    x = 107,512.95/280.42
  6. Step 6: Final answer
    x = 383.40

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.