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Finding the Fourth Proportional to 160.80, 240.80 and 128.80

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Solution

The fourth proportional to 160.80, 240.80 and 128.80 is: 192.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    160.80 : 240.80 = 128.80 : x
  2. Step 2: Convert to fraction form
    160.80/240.80 = 128.80/x
  3. Step 3: Cross multiply
    160.80x = 240.80 × 128.80
  4. Step 4: Simplify right side
    160.80x = 31,015.04
  5. Step 5: Solve for x
    x = 31,015.04/160.80
  6. Step 6: Final answer
    x = 192.88

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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.