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Finding the Fourth Proportional to 101.68, 152.38 and 81.30

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Solution

The fourth proportional to 101.68, 152.38 and 81.30 is: 121.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.68 : 152.38 = 81.30 : x
  2. Step 2: Convert to fraction form
    101.68/152.38 = 81.30/x
  3. Step 3: Cross multiply
    101.68x = 152.38 × 81.30
  4. Step 4: Simplify right side
    101.68x = 12,388.49
  5. Step 5: Solve for x
    x = 12,388.49/101.68
  6. Step 6: Final answer
    x = 121.84

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.