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Finding the Fourth Proportional to 85.79, 127.76 and 83.66

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Solution

The fourth proportional to 85.79, 127.76 and 83.66 is: 124.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.79 : 127.76 = 83.66 : x
  2. Step 2: Convert to fraction form
    85.79/127.76 = 83.66/x
  3. Step 3: Cross multiply
    85.79x = 127.76 × 83.66
  4. Step 4: Simplify right side
    85.79x = 10,688.40
  5. Step 5: Solve for x
    x = 10,688.40/85.79
  6. Step 6: Final answer
    x = 124.59

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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.