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Finding the Fourth Proportional to 628.20, 942.30 and 445.95

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Solution

The fourth proportional to 628.20, 942.30 and 445.95 is: 668.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.20 : 942.30 = 445.95 : x
  2. Step 2: Convert to fraction form
    628.20/942.30 = 445.95/x
  3. Step 3: Cross multiply
    628.20x = 942.30 × 445.95
  4. Step 4: Simplify right side
    628.20x = 420,218.69
  5. Step 5: Solve for x
    x = 420,218.69/628.20
  6. Step 6: Final answer
    x = 668.93

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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.