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Finding the Fourth Proportional to 79.31, 109.38 and 68.18

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Solution

The fourth proportional to 79.31, 109.38 and 68.18 is: 94.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.31 : 109.38 = 68.18 : x
  2. Step 2: Convert to fraction form
    79.31/109.38 = 68.18/x
  3. Step 3: Cross multiply
    79.31x = 109.38 × 68.18
  4. Step 4: Simplify right side
    79.31x = 7,457.24
  5. Step 5: Solve for x
    x = 7,457.24/79.31
  6. Step 6: Final answer
    x = 94.02

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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.