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Finding the Fourth Proportional to 680.19, 1,020.68 and 406.81

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Solution

The fourth proportional to 680.19, 1,020.68 and 406.81 is: 610.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.19 : 1,020.68 = 406.81 : x
  2. Step 2: Convert to fraction form
    680.19/1,020.68 = 406.81/x
  3. Step 3: Cross multiply
    680.19x = 1,020.68 × 406.81
  4. Step 4: Simplify right side
    680.19x = 415,222.83
  5. Step 5: Solve for x
    x = 415,222.83/680.19
  6. Step 6: Final answer
    x = 610.45

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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.