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Finding the Fourth Proportional to 228.30, 315.27 and 209.40

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Solution

The fourth proportional to 228.30, 315.27 and 209.40 is: 289.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    228.30 : 315.27 = 209.40 : x
  2. Step 2: Convert to fraction form
    228.30/315.27 = 209.40/x
  3. Step 3: Cross multiply
    228.30x = 315.27 × 209.40
  4. Step 4: Simplify right side
    228.30x = 66,017.54
  5. Step 5: Solve for x
    x = 66,017.54/228.30
  6. Step 6: Final answer
    x = 289.17

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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.