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Finding the Fourth Proportional to 680.16, 1,021.62 and 406.78

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Solution

The fourth proportional to 680.16, 1,021.62 and 406.78 is: 611.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.16 : 1,021.62 = 406.78 : x
  2. Step 2: Convert to fraction form
    680.16/1,021.62 = 406.78/x
  3. Step 3: Cross multiply
    680.16x = 1,021.62 × 406.78
  4. Step 4: Simplify right side
    680.16x = 415,574.58
  5. Step 5: Solve for x
    x = 415,574.58/680.16
  6. Step 6: Final answer
    x = 611.00

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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.