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Finding the Fourth Proportional to 278.79, 418.28 and 206.79

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Solution

The fourth proportional to 278.79, 418.28 and 206.79 is: 310.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.79 : 418.28 = 206.79 : x
  2. Step 2: Convert to fraction form
    278.79/418.28 = 206.79/x
  3. Step 3: Cross multiply
    278.79x = 418.28 × 206.79
  4. Step 4: Simplify right side
    278.79x = 86,495.09
  5. Step 5: Solve for x
    x = 86,495.09/278.79
  6. Step 6: Final answer
    x = 310.25

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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.