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Finding the Fourth Proportional to 279.70, 419.10 and 206.80

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Solution

The fourth proportional to 279.70, 419.10 and 206.80 is: 309.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.70 : 419.10 = 206.80 : x
  2. Step 2: Convert to fraction form
    279.70/419.10 = 206.80/x
  3. Step 3: Cross multiply
    279.70x = 419.10 × 206.80
  4. Step 4: Simplify right side
    279.70x = 86,669.88
  5. Step 5: Solve for x
    x = 86,669.88/279.70
  6. Step 6: Final answer
    x = 309.87

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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.