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Finding the Fourth Proportional to 28.21, 42.12 and 22.18

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Solution

The fourth proportional to 28.21, 42.12 and 22.18 is: 33.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.21 : 42.12 = 22.18 : x
  2. Step 2: Convert to fraction form
    28.21/42.12 = 22.18/x
  3. Step 3: Cross multiply
    28.21x = 42.12 × 22.18
  4. Step 4: Simplify right side
    28.21x = 934.22
  5. Step 5: Solve for x
    x = 934.22/28.21
  6. Step 6: Final answer
    x = 33.12

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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.