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Finding the Fourth Proportional to 84.21, 127.02 and 79.22

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Solution

The fourth proportional to 84.21, 127.02 and 79.22 is: 119.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.21 : 127.02 = 79.22 : x
  2. Step 2: Convert to fraction form
    84.21/127.02 = 79.22/x
  3. Step 3: Cross multiply
    84.21x = 127.02 × 79.22
  4. Step 4: Simplify right side
    84.21x = 10,061.89
  5. Step 5: Solve for x
    x = 10,061.89/84.21
  6. Step 6: Final answer
    x = 119.49

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.