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Finding the Fourth Proportional to 280.78, 386.84 and 210.73

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Solution

The fourth proportional to 280.78, 386.84 and 210.73 is: 290.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.78 : 386.84 = 210.73 : x
  2. Step 2: Convert to fraction form
    280.78/386.84 = 210.73/x
  3. Step 3: Cross multiply
    280.78x = 386.84 × 210.73
  4. Step 4: Simplify right side
    280.78x = 81,516.86
  5. Step 5: Solve for x
    x = 81,516.86/280.78
  6. Step 6: Final answer
    x = 290.33

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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.