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Finding the Fourth Proportional to 28.30, 38.72 and 28.03

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Solution

The fourth proportional to 28.30, 38.72 and 28.03 is: 38.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.30 : 38.72 = 28.03 : x
  2. Step 2: Convert to fraction form
    28.30/38.72 = 28.03/x
  3. Step 3: Cross multiply
    28.30x = 38.72 × 28.03
  4. Step 4: Simplify right side
    28.30x = 1,085.32
  5. Step 5: Solve for x
    x = 1,085.32/28.30
  6. Step 6: Final answer
    x = 38.35

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.