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Finding the Fourth Proportional to 279.89, 386.27 and 209.82

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Solution

The fourth proportional to 279.89, 386.27 and 209.82 is: 289.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.89 : 386.27 = 209.82 : x
  2. Step 2: Convert to fraction form
    279.89/386.27 = 209.82/x
  3. Step 3: Cross multiply
    279.89x = 386.27 × 209.82
  4. Step 4: Simplify right side
    279.89x = 81,047.17
  5. Step 5: Solve for x
    x = 81,047.17/279.89
  6. Step 6: Final answer
    x = 289.57

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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.