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Finding the Fourth Proportional to 137.40, 189.70 and 123.54

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Solution

The fourth proportional to 137.40, 189.70 and 123.54 is: 170.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.40 : 189.70 = 123.54 : x
  2. Step 2: Convert to fraction form
    137.40/189.70 = 123.54/x
  3. Step 3: Cross multiply
    137.40x = 189.70 × 123.54
  4. Step 4: Simplify right side
    137.40x = 23,435.54
  5. Step 5: Solve for x
    x = 23,435.54/137.40
  6. Step 6: Final answer
    x = 170.56

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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.