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Finding the Fourth Proportional to 154.01, 212.40 and 121.20

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Solution

The fourth proportional to 154.01, 212.40 and 121.20 is: 167.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.01 : 212.40 = 121.20 : x
  2. Step 2: Convert to fraction form
    154.01/212.40 = 121.20/x
  3. Step 3: Cross multiply
    154.01x = 212.40 × 121.20
  4. Step 4: Simplify right side
    154.01x = 25,742.88
  5. Step 5: Solve for x
    x = 25,742.88/154.01
  6. Step 6: Final answer
    x = 167.16

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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.