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Finding the Fourth Proportional to 85.71, 127.86 and 83.10

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Solution

The fourth proportional to 85.71, 127.86 and 83.10 is: 123.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.71 : 127.86 = 83.10 : x
  2. Step 2: Convert to fraction form
    85.71/127.86 = 83.10/x
  3. Step 3: Cross multiply
    85.71x = 127.86 × 83.10
  4. Step 4: Simplify right side
    85.71x = 10,625.17
  5. Step 5: Solve for x
    x = 10,625.17/85.71
  6. Step 6: Final answer
    x = 123.97

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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.