Home / 1,280.67-1,921.00-415.05

Finding the Fourth Proportional to 1,280.67, 1,921.00 and 415.05

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Solution

The fourth proportional to 1,280.67, 1,921.00 and 415.05 is: 622.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.67 : 1,921.00 = 415.05 : x
  2. Step 2: Convert to fraction form
    1,280.67/1,921.00 = 415.05/x
  3. Step 3: Cross multiply
    1,280.67x = 1,921.00 × 415.05
  4. Step 4: Simplify right side
    1,280.67x = 797,300.41
  5. Step 5: Solve for x
    x = 797,300.41/1,280.67
  6. Step 6: Final answer
    x = 622.57

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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.