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Finding the Fourth Proportional to 149.30, 205.90 and 107.78

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Solution

The fourth proportional to 149.30, 205.90 and 107.78 is: 148.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    149.30 : 205.90 = 107.78 : x
  2. Step 2: Convert to fraction form
    149.30/205.90 = 107.78/x
  3. Step 3: Cross multiply
    149.30x = 205.90 × 107.78
  4. Step 4: Simplify right side
    149.30x = 22,192.15
  5. Step 5: Solve for x
    x = 22,192.15/149.30
  6. Step 6: Final answer
    x = 148.65

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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.