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Finding the Fourth Proportional to 419.91, 579.60 and 280.05

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Solution

The fourth proportional to 419.91, 579.60 and 280.05 is: 386.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.91 : 579.60 = 280.05 : x
  2. Step 2: Convert to fraction form
    419.91/579.60 = 280.05/x
  3. Step 3: Cross multiply
    419.91x = 579.60 × 280.05
  4. Step 4: Simplify right side
    419.91x = 162,316.98
  5. Step 5: Solve for x
    x = 162,316.98/419.91
  6. Step 6: Final answer
    x = 386.55

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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.