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Finding the Fourth Proportional to 120.82, 180.90 and 84.82

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Solution

The fourth proportional to 120.82, 180.90 and 84.82 is: 127.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.82 : 180.90 = 84.82 : x
  2. Step 2: Convert to fraction form
    120.82/180.90 = 84.82/x
  3. Step 3: Cross multiply
    120.82x = 180.90 × 84.82
  4. Step 4: Simplify right side
    120.82x = 15,343.03
  5. Step 5: Solve for x
    x = 15,343.03/120.82
  6. Step 6: Final answer
    x = 127.00

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.