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Finding the Fourth Proportional to 28.30, 39.06 and 15.36

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Solution

The fourth proportional to 28.30, 39.06 and 15.36 is: 21.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.30 : 39.06 = 15.36 : x
  2. Step 2: Convert to fraction form
    28.30/39.06 = 15.36/x
  3. Step 3: Cross multiply
    28.30x = 39.06 × 15.36
  4. Step 4: Simplify right side
    28.30x = 600.02
  5. Step 5: Solve for x
    x = 600.02/28.30
  6. Step 6: Final answer
    x = 21.20

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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.