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Finding the Fourth Proportional to 1,680.81, 2,520.81 and 640.44

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Solution

The fourth proportional to 1,680.81, 2,520.81 and 640.44 is: 960.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,680.81 : 2,520.81 = 640.44 : x
  2. Step 2: Convert to fraction form
    1,680.81/2,520.81 = 640.44/x
  3. Step 3: Cross multiply
    1,680.81x = 2,520.81 × 640.44
  4. Step 4: Simplify right side
    1,680.81x = 1,614,427.56
  5. Step 5: Solve for x
    x = 1,614,427.56/1,680.81
  6. Step 6: Final answer
    x = 960.51

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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.