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Finding the Fourth Proportional to 154.33, 212.85 and 123.20

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Solution

The fourth proportional to 154.33, 212.85 and 123.20 is: 169.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.33 : 212.85 = 123.20 : x
  2. Step 2: Convert to fraction form
    154.33/212.85 = 123.20/x
  3. Step 3: Cross multiply
    154.33x = 212.85 × 123.20
  4. Step 4: Simplify right side
    154.33x = 26,223.12
  5. Step 5: Solve for x
    x = 26,223.12/154.33
  6. Step 6: Final answer
    x = 169.92

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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.