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Finding the Fourth Proportional to 154.80, 213.60 and 89.31

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Solution

The fourth proportional to 154.80, 213.60 and 89.31 is: 123.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.80 : 213.60 = 89.31 : x
  2. Step 2: Convert to fraction form
    154.80/213.60 = 89.31/x
  3. Step 3: Cross multiply
    154.80x = 213.60 × 89.31
  4. Step 4: Simplify right side
    154.80x = 19,076.62
  5. Step 5: Solve for x
    x = 19,076.62/154.80
  6. Step 6: Final answer
    x = 123.23

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.