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Finding the Fourth Proportional to 680.02, 1,019.52 and 420.07

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Solution

The fourth proportional to 680.02, 1,019.52 and 420.07 is: 629.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.02 : 1,019.52 = 420.07 : x
  2. Step 2: Convert to fraction form
    680.02/1,019.52 = 420.07/x
  3. Step 3: Cross multiply
    680.02x = 1,019.52 × 420.07
  4. Step 4: Simplify right side
    680.02x = 428,269.77
  5. Step 5: Solve for x
    x = 428,269.77/680.02
  6. Step 6: Final answer
    x = 629.79

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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.