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Finding the Fourth Proportional to 109.28, 164.04 and 68.72

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Solution

The fourth proportional to 109.28, 164.04 and 68.72 is: 103.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    109.28 : 164.04 = 68.72 : x
  2. Step 2: Convert to fraction form
    109.28/164.04 = 68.72/x
  3. Step 3: Cross multiply
    109.28x = 164.04 × 68.72
  4. Step 4: Simplify right side
    109.28x = 11,272.37
  5. Step 5: Solve for x
    x = 11,272.37/109.28
  6. Step 6: Final answer
    x = 103.16

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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.