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Finding the Fourth Proportional to 209.81, 289.28 and 191.31

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Solution

The fourth proportional to 209.81, 289.28 and 191.31 is: 263.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.81 : 289.28 = 191.31 : x
  2. Step 2: Convert to fraction form
    209.81/289.28 = 191.31/x
  3. Step 3: Cross multiply
    209.81x = 289.28 × 191.31
  4. Step 4: Simplify right side
    209.81x = 55,341.20
  5. Step 5: Solve for x
    x = 55,341.20/209.81
  6. Step 6: Final answer
    x = 263.77

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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.