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Finding the Fourth Proportional to 45.05, 67.19 and 42.21

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Solution

The fourth proportional to 45.05, 67.19 and 42.21 is: 62.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.05 : 67.19 = 42.21 : x
  2. Step 2: Convert to fraction form
    45.05/67.19 = 42.21/x
  3. Step 3: Cross multiply
    45.05x = 67.19 × 42.21
  4. Step 4: Simplify right side
    45.05x = 2,835.88
  5. Step 5: Solve for x
    x = 2,835.88/45.05
  6. Step 6: Final answer
    x = 62.96

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.