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Finding the Fourth Proportional to 2,660, 3,989.28 and 905.06

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Solution

The fourth proportional to 2,660, 3,989.28 and 905.06 is: 1,357.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,660 : 3,989.28 = 905.06 : x
  2. Step 2: Convert to fraction form
    2,660/3,989.28 = 905.06/x
  3. Step 3: Cross multiply
    2,660x = 3,989.28 × 905.06
  4. Step 4: Simplify right side
    2,660x = 3,610,537.76
  5. Step 5: Solve for x
    x = 3,610,537.76/2,660
  6. Step 6: Final answer
    x = 1,357.35

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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.