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Finding the Fourth Proportional to 280.71, 420.80 and 263.43

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Solution

The fourth proportional to 280.71, 420.80 and 263.43 is: 394.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.71 : 420.80 = 263.43 : x
  2. Step 2: Convert to fraction form
    280.71/420.80 = 263.43/x
  3. Step 3: Cross multiply
    280.71x = 420.80 × 263.43
  4. Step 4: Simplify right side
    280.71x = 110,850.03
  5. Step 5: Solve for x
    x = 110,850.03/280.71
  6. Step 6: Final answer
    x = 394.89

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.