Home / 1,280.56-1,921.80-511.12

Finding the Fourth Proportional to 1,280.56, 1,921.80 and 511.12

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Solution

The fourth proportional to 1,280.56, 1,921.80 and 511.12 is: 767.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.56 : 1,921.80 = 511.12 : x
  2. Step 2: Convert to fraction form
    1,280.56/1,921.80 = 511.12/x
  3. Step 3: Cross multiply
    1,280.56x = 1,921.80 × 511.12
  4. Step 4: Simplify right side
    1,280.56x = 982,270.42
  5. Step 5: Solve for x
    x = 982,270.42/1,280.56
  6. Step 6: Final answer
    x = 767.06

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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.