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Finding the Fourth Proportional to 28.55, 39.40 and 16.90

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Solution

The fourth proportional to 28.55, 39.40 and 16.90 is: 23.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.55 : 39.40 = 16.90 : x
  2. Step 2: Convert to fraction form
    28.55/39.40 = 16.90/x
  3. Step 3: Cross multiply
    28.55x = 39.40 × 16.90
  4. Step 4: Simplify right side
    28.55x = 665.86
  5. Step 5: Solve for x
    x = 665.86/28.55
  6. Step 6: Final answer
    x = 23.32

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.