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Finding the Fourth Proportional to 1,640.20, 2,458.68 and 665.80

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Solution

The fourth proportional to 1,640.20, 2,458.68 and 665.80 is: 998.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,640.20 : 2,458.68 = 665.80 : x
  2. Step 2: Convert to fraction form
    1,640.20/2,458.68 = 665.80/x
  3. Step 3: Cross multiply
    1,640.20x = 2,458.68 × 665.80
  4. Step 4: Simplify right side
    1,640.20x = 1,636,989.14
  5. Step 5: Solve for x
    x = 1,636,989.14/1,640.20
  6. Step 6: Final answer
    x = 998.04

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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.