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Finding the Fourth Proportional to 82.09, 113.21 and 72.19

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Solution

The fourth proportional to 82.09, 113.21 and 72.19 is: 99.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.09 : 113.21 = 72.19 : x
  2. Step 2: Convert to fraction form
    82.09/113.21 = 72.19/x
  3. Step 3: Cross multiply
    82.09x = 113.21 × 72.19
  4. Step 4: Simplify right side
    82.09x = 8,172.27
  5. Step 5: Solve for x
    x = 8,172.27/82.09
  6. Step 6: Final answer
    x = 99.55

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.