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Finding the Fourth Proportional to 86.21, 118.87 and 70.62

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Solution

The fourth proportional to 86.21, 118.87 and 70.62 is: 97.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.21 : 118.87 = 70.62 : x
  2. Step 2: Convert to fraction form
    86.21/118.87 = 70.62/x
  3. Step 3: Cross multiply
    86.21x = 118.87 × 70.62
  4. Step 4: Simplify right side
    86.21x = 8,394.39
  5. Step 5: Solve for x
    x = 8,394.39/86.21
  6. Step 6: Final answer
    x = 97.37

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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.