Home / 1,280.26-1,920.30-458.38

Finding the Fourth Proportional to 1,280.26, 1,920.30 and 458.38

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Solution

The fourth proportional to 1,280.26, 1,920.30 and 458.38 is: 687.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.26 : 1,920.30 = 458.38 : x
  2. Step 2: Convert to fraction form
    1,280.26/1,920.30 = 458.38/x
  3. Step 3: Cross multiply
    1,280.26x = 1,920.30 × 458.38
  4. Step 4: Simplify right side
    1,280.26x = 880,227.11
  5. Step 5: Solve for x
    x = 880,227.11/1,280.26
  6. Step 6: Final answer
    x = 687.54

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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.