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Finding the Fourth Proportional to 2,660, 3,990.64 and 836

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Solution

The fourth proportional to 2,660, 3,990.64 and 836 is: 1,254.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,660 : 3,990.64 = 836 : x
  2. Step 2: Convert to fraction form
    2,660/3,990.64 = 836/x
  3. Step 3: Cross multiply
    2,660x = 3,990.64 × 836
  4. Step 4: Simplify right side
    2,660x = 3,336,175.04
  5. Step 5: Solve for x
    x = 3,336,175.04/2,660
  6. Step 6: Final answer
    x = 1,254.20

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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.