Home / 1,285.25-1,916.82-1,220.85

Finding the Fourth Proportional to 1,285.25, 1,916.82 and 1,220.85

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Solution

The fourth proportional to 1,285.25, 1,916.82 and 1,220.85 is: 1,820.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.25 : 1,916.82 = 1,220.85 : x
  2. Step 2: Convert to fraction form
    1,285.25/1,916.82 = 1,220.85/x
  3. Step 3: Cross multiply
    1,285.25x = 1,916.82 × 1,220.85
  4. Step 4: Simplify right side
    1,285.25x = 2,340,149.70
  5. Step 5: Solve for x
    x = 2,340,149.70/1,285.25
  6. Step 6: Final answer
    x = 1,820.78

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.