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Finding the Fourth Proportional to 120.40, 180.62 and 39.23

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Solution

The fourth proportional to 120.40, 180.62 and 39.23 is: 58.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.40 : 180.62 = 39.23 : x
  2. Step 2: Convert to fraction form
    120.40/180.62 = 39.23/x
  3. Step 3: Cross multiply
    120.40x = 180.62 × 39.23
  4. Step 4: Simplify right side
    120.40x = 7,086.41
  5. Step 5: Solve for x
    x = 7,086.41/120.40
  6. Step 6: Final answer
    x = 58.86

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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.