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Finding the Fourth Proportional to 103.21, 155.05 and 99.56

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Solution

The fourth proportional to 103.21, 155.05 and 99.56 is: 149.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.21 : 155.05 = 99.56 : x
  2. Step 2: Convert to fraction form
    103.21/155.05 = 99.56/x
  3. Step 3: Cross multiply
    103.21x = 155.05 × 99.56
  4. Step 4: Simplify right side
    103.21x = 15,436.92
  5. Step 5: Solve for x
    x = 15,436.92/103.21
  6. Step 6: Final answer
    x = 149.57

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.