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Finding the Fourth Proportional to 1,680.09, 2,520.33 and 640.88

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Solution

The fourth proportional to 1,680.09, 2,520.33 and 640.88 is: 961.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,680.09 : 2,520.33 = 640.88 : x
  2. Step 2: Convert to fraction form
    1,680.09/2,520.33 = 640.88/x
  3. Step 3: Cross multiply
    1,680.09x = 2,520.33 × 640.88
  4. Step 4: Simplify right side
    1,680.09x = 1,615,216.49
  5. Step 5: Solve for x
    x = 1,615,216.49/1,680.09
  6. Step 6: Final answer
    x = 961.39

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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.