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Finding the Fourth Proportional to 154.80, 213.50 and 123.72

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Solution

The fourth proportional to 154.80, 213.50 and 123.72 is: 170.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.80 : 213.50 = 123.72 : x
  2. Step 2: Convert to fraction form
    154.80/213.50 = 123.72/x
  3. Step 3: Cross multiply
    154.80x = 213.50 × 123.72
  4. Step 4: Simplify right side
    154.80x = 26,413.15
  5. Step 5: Solve for x
    x = 26,413.15/154.80
  6. Step 6: Final answer
    x = 170.63

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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.