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Finding the Fourth Proportional to 490, 676.19 and 280.19

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Solution

The fourth proportional to 490, 676.19 and 280.19 is: 386.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    490 : 676.19 = 280.19 : x
  2. Step 2: Convert to fraction form
    490/676.19 = 280.19/x
  3. Step 3: Cross multiply
    490x = 676.19 × 280.19
  4. Step 4: Simplify right side
    490x = 189,461.68
  5. Step 5: Solve for x
    x = 189,461.68/490
  6. Step 6: Final answer
    x = 386.66

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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.