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Finding the Fourth Proportional to 86.70, 119.60 and 68.25

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Solution

The fourth proportional to 86.70, 119.60 and 68.25 is: 94.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.70 : 119.60 = 68.25 : x
  2. Step 2: Convert to fraction form
    86.70/119.60 = 68.25/x
  3. Step 3: Cross multiply
    86.70x = 119.60 × 68.25
  4. Step 4: Simplify right side
    86.70x = 8,162.70
  5. Step 5: Solve for x
    x = 8,162.70/86.70
  6. Step 6: Final answer
    x = 94.15

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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.