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Finding the Fourth Proportional to 228.72, 315.27 and 209.90

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Solution

The fourth proportional to 228.72, 315.27 and 209.90 is: 289.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    228.72 : 315.27 = 209.90 : x
  2. Step 2: Convert to fraction form
    228.72/315.27 = 209.90/x
  3. Step 3: Cross multiply
    228.72x = 315.27 × 209.90
  4. Step 4: Simplify right side
    228.72x = 66,173.60
  5. Step 5: Solve for x
    x = 66,173.60/228.72
  6. Step 6: Final answer
    x = 289.32

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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.