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Finding the Fourth Proportional to 79.79, 109.77 and 69.39

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Solution

The fourth proportional to 79.79, 109.77 and 69.39 is: 95.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.79 : 109.77 = 69.39 : x
  2. Step 2: Convert to fraction form
    79.79/109.77 = 69.39/x
  3. Step 3: Cross multiply
    79.79x = 109.77 × 69.39
  4. Step 4: Simplify right side
    79.79x = 7,616.94
  5. Step 5: Solve for x
    x = 7,616.94/79.79
  6. Step 6: Final answer
    x = 95.47

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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.