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Finding the Fourth Proportional to 84.15, 125.71 and 83.75

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Solution

The fourth proportional to 84.15, 125.71 and 83.75 is: 125.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.15 : 125.71 = 83.75 : x
  2. Step 2: Convert to fraction form
    84.15/125.71 = 83.75/x
  3. Step 3: Cross multiply
    84.15x = 125.71 × 83.75
  4. Step 4: Simplify right side
    84.15x = 10,527.37
  5. Step 5: Solve for x
    x = 10,527.37/84.15
  6. Step 6: Final answer
    x = 125.10

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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.