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Finding the Fourth Proportional to 190.80, 286.47 and 142.20

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Solution

The fourth proportional to 190.80, 286.47 and 142.20 is: 213.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    190.80 : 286.47 = 142.20 : x
  2. Step 2: Convert to fraction form
    190.80/286.47 = 142.20/x
  3. Step 3: Cross multiply
    190.80x = 286.47 × 142.20
  4. Step 4: Simplify right side
    190.80x = 40,736.03
  5. Step 5: Solve for x
    x = 40,736.03/190.80
  6. Step 6: Final answer
    x = 213.50

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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.