Home / 1,081.27-1,621.09-431.65

Finding the Fourth Proportional to 1,081.27, 1,621.09 and 431.65

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Solution

The fourth proportional to 1,081.27, 1,621.09 and 431.65 is: 647.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,081.27 : 1,621.09 = 431.65 : x
  2. Step 2: Convert to fraction form
    1,081.27/1,621.09 = 431.65/x
  3. Step 3: Cross multiply
    1,081.27x = 1,621.09 × 431.65
  4. Step 4: Simplify right side
    1,081.27x = 699,743.50
  5. Step 5: Solve for x
    x = 699,743.50/1,081.27
  6. Step 6: Final answer
    x = 647.15

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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.