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Finding the Fourth Proportional to 154.21, 212.85 and 101.79

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Solution

The fourth proportional to 154.21, 212.85 and 101.79 is: 140.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.21 : 212.85 = 101.79 : x
  2. Step 2: Convert to fraction form
    154.21/212.85 = 101.79/x
  3. Step 3: Cross multiply
    154.21x = 212.85 × 101.79
  4. Step 4: Simplify right side
    154.21x = 21,666.00
  5. Step 5: Solve for x
    x = 21,666.00/154.21
  6. Step 6: Final answer
    x = 140.50

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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.