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Finding the Fourth Proportional to 1,277.80, 1,916.49 and 412

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Solution

The fourth proportional to 1,277.80, 1,916.49 and 412 is: 617.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,277.80 : 1,916.49 = 412 : x
  2. Step 2: Convert to fraction form
    1,277.80/1,916.49 = 412/x
  3. Step 3: Cross multiply
    1,277.80x = 1,916.49 × 412
  4. Step 4: Simplify right side
    1,277.80x = 789,593.88
  5. Step 5: Solve for x
    x = 789,593.88/1,277.80
  6. Step 6: Final answer
    x = 617.93

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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.