Home / 1,280.57-1,919.97-630.81

Finding the Fourth Proportional to 1,280.57, 1,919.97 and 630.81

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Solution

The fourth proportional to 1,280.57, 1,919.97 and 630.81 is: 945.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.57 : 1,919.97 = 630.81 : x
  2. Step 2: Convert to fraction form
    1,280.57/1,919.97 = 630.81/x
  3. Step 3: Cross multiply
    1,280.57x = 1,919.97 × 630.81
  4. Step 4: Simplify right side
    1,280.57x = 1,211,136.28
  5. Step 5: Solve for x
    x = 1,211,136.28/1,280.57
  6. Step 6: Final answer
    x = 945.78

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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.