Home / 1,280.50-1,921.23-511.06

Finding the Fourth Proportional to 1,280.50, 1,921.23 and 511.06

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Solution

The fourth proportional to 1,280.50, 1,921.23 and 511.06 is: 766.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.50 : 1,921.23 = 511.06 : x
  2. Step 2: Convert to fraction form
    1,280.50/1,921.23 = 511.06/x
  3. Step 3: Cross multiply
    1,280.50x = 1,921.23 × 511.06
  4. Step 4: Simplify right side
    1,280.50x = 981,863.80
  5. Step 5: Solve for x
    x = 981,863.80/1,280.50
  6. Step 6: Final answer
    x = 766.78

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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.