Home / 1,285.98-1,929.26-420.09

Finding the Fourth Proportional to 1,285.98, 1,929.26 and 420.09

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Solution

The fourth proportional to 1,285.98, 1,929.26 and 420.09 is: 630.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.98 : 1,929.26 = 420.09 : x
  2. Step 2: Convert to fraction form
    1,285.98/1,929.26 = 420.09/x
  3. Step 3: Cross multiply
    1,285.98x = 1,929.26 × 420.09
  4. Step 4: Simplify right side
    1,285.98x = 810,462.83
  5. Step 5: Solve for x
    x = 810,462.83/1,285.98
  6. Step 6: Final answer
    x = 630.23

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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.