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Finding the Fourth Proportional to 1,309.91, 1,807.66 and 779.15

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Solution

The fourth proportional to 1,309.91, 1,807.66 and 779.15 is: 1,075.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,309.91 : 1,807.66 = 779.15 : x
  2. Step 2: Convert to fraction form
    1,309.91/1,807.66 = 779.15/x
  3. Step 3: Cross multiply
    1,309.91x = 1,807.66 × 779.15
  4. Step 4: Simplify right side
    1,309.91x = 1,408,438.29
  5. Step 5: Solve for x
    x = 1,408,438.29/1,309.91
  6. Step 6: Final answer
    x = 1,075.22

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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.