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Finding the Fourth Proportional to 155.51, 213.17 and 155.21

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Solution

The fourth proportional to 155.51, 213.17 and 155.21 is: 212.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.51 : 213.17 = 155.21 : x
  2. Step 2: Convert to fraction form
    155.51/213.17 = 155.21/x
  3. Step 3: Cross multiply
    155.51x = 213.17 × 155.21
  4. Step 4: Simplify right side
    155.51x = 33,084.27
  5. Step 5: Solve for x
    x = 33,084.27/155.51
  6. Step 6: Final answer
    x = 212.75

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.