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Finding the Fourth Proportional to 680.32, 1,021.48 and 419.57

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Solution

The fourth proportional to 680.32, 1,021.48 and 419.57 is: 629.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.32 : 1,021.48 = 419.57 : x
  2. Step 2: Convert to fraction form
    680.32/1,021.48 = 419.57/x
  3. Step 3: Cross multiply
    680.32x = 1,021.48 × 419.57
  4. Step 4: Simplify right side
    680.32x = 428,577.26
  5. Step 5: Solve for x
    x = 428,577.26/680.32
  6. Step 6: Final answer
    x = 629.97

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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.