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Finding the Fourth Proportional to 102.85, 154.28 and 30.72

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Solution

The fourth proportional to 102.85, 154.28 and 30.72 is: 46.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.85 : 154.28 = 30.72 : x
  2. Step 2: Convert to fraction form
    102.85/154.28 = 30.72/x
  3. Step 3: Cross multiply
    102.85x = 154.28 × 30.72
  4. Step 4: Simplify right side
    102.85x = 4,739.56
  5. Step 5: Solve for x
    x = 4,739.56/102.85
  6. Step 6: Final answer
    x = 46.08

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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.