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Finding the Fourth Proportional to 85.09, 128.26 and 83.04

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Solution

The fourth proportional to 85.09, 128.26 and 83.04 is: 125.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.09 : 128.26 = 83.04 : x
  2. Step 2: Convert to fraction form
    85.09/128.26 = 83.04/x
  3. Step 3: Cross multiply
    85.09x = 128.26 × 83.04
  4. Step 4: Simplify right side
    85.09x = 10,650.28
  5. Step 5: Solve for x
    x = 10,650.28/85.09
  6. Step 6: Final answer
    x = 125.17

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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.