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Finding the Fourth Proportional to 120.58, 180.82 and 90.34

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Solution

The fourth proportional to 120.58, 180.82 and 90.34 is: 135.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.58 : 180.82 = 90.34 : x
  2. Step 2: Convert to fraction form
    120.58/180.82 = 90.34/x
  3. Step 3: Cross multiply
    120.58x = 180.82 × 90.34
  4. Step 4: Simplify right side
    120.58x = 16,335.28
  5. Step 5: Solve for x
    x = 16,335.28/120.58
  6. Step 6: Final answer
    x = 135.47

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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.