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Finding the Fourth Proportional to 228.86, 315.71 and 155.21

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Solution

The fourth proportional to 228.86, 315.71 and 155.21 is: 214.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    228.86 : 315.71 = 155.21 : x
  2. Step 2: Convert to fraction form
    228.86/315.71 = 155.21/x
  3. Step 3: Cross multiply
    228.86x = 315.71 × 155.21
  4. Step 4: Simplify right side
    228.86x = 49,000.45
  5. Step 5: Solve for x
    x = 49,000.45/228.86
  6. Step 6: Final answer
    x = 214.10

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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.