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Finding the Fourth Proportional to 280.15, 386.28 and 209.27

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Solution

The fourth proportional to 280.15, 386.28 and 209.27 is: 288.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.15 : 386.28 = 209.27 : x
  2. Step 2: Convert to fraction form
    280.15/386.28 = 209.27/x
  3. Step 3: Cross multiply
    280.15x = 386.28 × 209.27
  4. Step 4: Simplify right side
    280.15x = 80,837.78
  5. Step 5: Solve for x
    x = 80,837.78/280.15
  6. Step 6: Final answer
    x = 288.55

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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.