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Finding the Fourth Proportional to 85.69, 127.76 and 83.08

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Solution

The fourth proportional to 85.69, 127.76 and 83.08 is: 123.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.69 : 127.76 = 83.08 : x
  2. Step 2: Convert to fraction form
    85.69/127.76 = 83.08/x
  3. Step 3: Cross multiply
    85.69x = 127.76 × 83.08
  4. Step 4: Simplify right side
    85.69x = 10,614.30
  5. Step 5: Solve for x
    x = 10,614.30/85.69
  6. Step 6: Final answer
    x = 123.87

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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.