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Finding the Fourth Proportional to 279.32, 418.91 and 206.21

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Solution

The fourth proportional to 279.32, 418.91 and 206.21 is: 309.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.32 : 418.91 = 206.21 : x
  2. Step 2: Convert to fraction form
    279.32/418.91 = 206.21/x
  3. Step 3: Cross multiply
    279.32x = 418.91 × 206.21
  4. Step 4: Simplify right side
    279.32x = 86,383.45
  5. Step 5: Solve for x
    x = 86,383.45/279.32
  6. Step 6: Final answer
    x = 309.27

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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.