Home / 1,280.89-1,921.71-415.18

Finding the Fourth Proportional to 1,280.89, 1,921.71 and 415.18

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Solution

The fourth proportional to 1,280.89, 1,921.71 and 415.18 is: 622.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.89 : 1,921.71 = 415.18 : x
  2. Step 2: Convert to fraction form
    1,280.89/1,921.71 = 415.18/x
  3. Step 3: Cross multiply
    1,280.89x = 1,921.71 × 415.18
  4. Step 4: Simplify right side
    1,280.89x = 797,855.56
  5. Step 5: Solve for x
    x = 797,855.56/1,280.89
  6. Step 6: Final answer
    x = 622.89

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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.