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Finding the Fourth Proportional to 281.14, 421.92 and 208.78

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Solution

The fourth proportional to 281.14, 421.92 and 208.78 is: 313.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.14 : 421.92 = 208.78 : x
  2. Step 2: Convert to fraction form
    281.14/421.92 = 208.78/x
  3. Step 3: Cross multiply
    281.14x = 421.92 × 208.78
  4. Step 4: Simplify right side
    281.14x = 88,088.46
  5. Step 5: Solve for x
    x = 88,088.46/281.14
  6. Step 6: Final answer
    x = 313.33

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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.