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Finding the Fourth Proportional to 85.29, 117.84 and 80.15

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Solution

The fourth proportional to 85.29, 117.84 and 80.15 is: 110.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.29 : 117.84 = 80.15 : x
  2. Step 2: Convert to fraction form
    85.29/117.84 = 80.15/x
  3. Step 3: Cross multiply
    85.29x = 117.84 × 80.15
  4. Step 4: Simplify right side
    85.29x = 9,444.88
  5. Step 5: Solve for x
    x = 9,444.88/85.29
  6. Step 6: Final answer
    x = 110.74

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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.