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Finding the Fourth Proportional to 85.17, 126.69 and 83.28

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Solution

The fourth proportional to 85.17, 126.69 and 83.28 is: 123.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.17 : 126.69 = 83.28 : x
  2. Step 2: Convert to fraction form
    85.17/126.69 = 83.28/x
  3. Step 3: Cross multiply
    85.17x = 126.69 × 83.28
  4. Step 4: Simplify right side
    85.17x = 10,550.74
  5. Step 5: Solve for x
    x = 10,550.74/85.17
  6. Step 6: Final answer
    x = 123.88

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.