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Finding the Fourth Proportional to 28.15, 42.21 and 16.75

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Solution

The fourth proportional to 28.15, 42.21 and 16.75 is: 25.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.15 : 42.21 = 16.75 : x
  2. Step 2: Convert to fraction form
    28.15/42.21 = 16.75/x
  3. Step 3: Cross multiply
    28.15x = 42.21 × 16.75
  4. Step 4: Simplify right side
    28.15x = 707.02
  5. Step 5: Solve for x
    x = 707.02/28.15
  6. Step 6: Final answer
    x = 25.12

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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.