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Finding the Fourth Proportional to 79.65, 119.88 and 69.75

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Solution

The fourth proportional to 79.65, 119.88 and 69.75 is: 104.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.65 : 119.88 = 69.75 : x
  2. Step 2: Convert to fraction form
    79.65/119.88 = 69.75/x
  3. Step 3: Cross multiply
    79.65x = 119.88 × 69.75
  4. Step 4: Simplify right side
    79.65x = 8,361.63
  5. Step 5: Solve for x
    x = 8,361.63/79.65
  6. Step 6: Final answer
    x = 104.98

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.