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Finding the Fourth Proportional to 100.25, 137.93 and 89.31

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Solution

The fourth proportional to 100.25, 137.93 and 89.31 is: 122.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.25 : 137.93 = 89.31 : x
  2. Step 2: Convert to fraction form
    100.25/137.93 = 89.31/x
  3. Step 3: Cross multiply
    100.25x = 137.93 × 89.31
  4. Step 4: Simplify right side
    100.25x = 12,318.08
  5. Step 5: Solve for x
    x = 12,318.08/100.25
  6. Step 6: Final answer
    x = 122.87

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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.