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Finding the Fourth Proportional to 403.81, 605.96 and 280.05

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Solution

The fourth proportional to 403.81, 605.96 and 280.05 is: 420.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.81 : 605.96 = 280.05 : x
  2. Step 2: Convert to fraction form
    403.81/605.96 = 280.05/x
  3. Step 3: Cross multiply
    403.81x = 605.96 × 280.05
  4. Step 4: Simplify right side
    403.81x = 169,699.80
  5. Step 5: Solve for x
    x = 169,699.80/403.81
  6. Step 6: Final answer
    x = 420.25

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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.