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Finding the Fourth Proportional to 279.96, 419.38 and 206.80

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Solution

The fourth proportional to 279.96, 419.38 and 206.80 is: 309.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.96 : 419.38 = 206.80 : x
  2. Step 2: Convert to fraction form
    279.96/419.38 = 206.80/x
  3. Step 3: Cross multiply
    279.96x = 419.38 × 206.80
  4. Step 4: Simplify right side
    279.96x = 86,727.78
  5. Step 5: Solve for x
    x = 86,727.78/279.96
  6. Step 6: Final answer
    x = 309.79

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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.