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Finding the Fourth Proportional to 146.79, 220.18 and 85.80

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Solution

The fourth proportional to 146.79, 220.18 and 85.80 is: 128.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    146.79 : 220.18 = 85.80 : x
  2. Step 2: Convert to fraction form
    146.79/220.18 = 85.80/x
  3. Step 3: Cross multiply
    146.79x = 220.18 × 85.80
  4. Step 4: Simplify right side
    146.79x = 18,891.44
  5. Step 5: Solve for x
    x = 18,891.44/146.79
  6. Step 6: Final answer
    x = 128.70

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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.