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Finding the Fourth Proportional to 680.89, 1,021.34 and 407.06

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Solution

The fourth proportional to 680.89, 1,021.34 and 407.06 is: 610.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.89 : 1,021.34 = 407.06 : x
  2. Step 2: Convert to fraction form
    680.89/1,021.34 = 407.06/x
  3. Step 3: Cross multiply
    680.89x = 1,021.34 × 407.06
  4. Step 4: Simplify right side
    680.89x = 415,749.85
  5. Step 5: Solve for x
    x = 415,749.85/680.89
  6. Step 6: Final answer
    x = 610.59

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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.