Home / 1,990.23-2,985.53-820.31

Finding the Fourth Proportional to 1,990.23, 2,985.53 and 820.31

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Solution

The fourth proportional to 1,990.23, 2,985.53 and 820.31 is: 1,230.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,990.23 : 2,985.53 = 820.31 : x
  2. Step 2: Convert to fraction form
    1,990.23/2,985.53 = 820.31/x
  3. Step 3: Cross multiply
    1,990.23x = 2,985.53 × 820.31
  4. Step 4: Simplify right side
    1,990.23x = 2,449,052.65
  5. Step 5: Solve for x
    x = 2,449,052.65/1,990.23
  6. Step 6: Final answer
    x = 1,230.54

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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.