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Finding the Fourth Proportional to 1,399.40, 2,099.79 and 577.91

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Solution

The fourth proportional to 1,399.40, 2,099.79 and 577.91 is: 867.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,399.40 : 2,099.79 = 577.91 : x
  2. Step 2: Convert to fraction form
    1,399.40/2,099.79 = 577.91/x
  3. Step 3: Cross multiply
    1,399.40x = 2,099.79 × 577.91
  4. Step 4: Simplify right side
    1,399.40x = 1,213,489.64
  5. Step 5: Solve for x
    x = 1,213,489.64/1,399.40
  6. Step 6: Final answer
    x = 867.15

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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.