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Finding the Fourth Proportional to 142.80, 215.34 and 133.80

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Solution

The fourth proportional to 142.80, 215.34 and 133.80 is: 201.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.80 : 215.34 = 133.80 : x
  2. Step 2: Convert to fraction form
    142.80/215.34 = 133.80/x
  3. Step 3: Cross multiply
    142.80x = 215.34 × 133.80
  4. Step 4: Simplify right side
    142.80x = 28,812.49
  5. Step 5: Solve for x
    x = 28,812.49/142.80
  6. Step 6: Final answer
    x = 201.77

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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.