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Finding the Fourth Proportional to 86.31, 119.30 and 65.62

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Solution

The fourth proportional to 86.31, 119.30 and 65.62 is: 90.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.31 : 119.30 = 65.62 : x
  2. Step 2: Convert to fraction form
    86.31/119.30 = 65.62/x
  3. Step 3: Cross multiply
    86.31x = 119.30 × 65.62
  4. Step 4: Simplify right side
    86.31x = 7,827.84
  5. Step 5: Solve for x
    x = 7,827.84/86.31
  6. Step 6: Final answer
    x = 90.70

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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.