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Finding the Fourth Proportional to 158.28, 218.32 and 121.54

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Solution

The fourth proportional to 158.28, 218.32 and 121.54 is: 167.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    158.28 : 218.32 = 121.54 : x
  2. Step 2: Convert to fraction form
    158.28/218.32 = 121.54/x
  3. Step 3: Cross multiply
    158.28x = 218.32 × 121.54
  4. Step 4: Simplify right side
    158.28x = 26,534.61
  5. Step 5: Solve for x
    x = 26,534.61/158.28
  6. Step 6: Final answer
    x = 167.64

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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.