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Finding the Fourth Proportional to 1,309.30, 1,808.43 and 979.19

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Solution

The fourth proportional to 1,309.30, 1,808.43 and 979.19 is: 1,352.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,309.30 : 1,808.43 = 979.19 : x
  2. Step 2: Convert to fraction form
    1,309.30/1,808.43 = 979.19/x
  3. Step 3: Cross multiply
    1,309.30x = 1,808.43 × 979.19
  4. Step 4: Simplify right side
    1,309.30x = 1,770,796.57
  5. Step 5: Solve for x
    x = 1,770,796.57/1,309.30
  6. Step 6: Final answer
    x = 1,352.48

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.