Home / 1,980.78-2,971.25-519.90

Finding the Fourth Proportional to 1,980.78, 2,971.25 and 519.90

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Solution

The fourth proportional to 1,980.78, 2,971.25 and 519.90 is: 779.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,980.78 : 2,971.25 = 519.90 : x
  2. Step 2: Convert to fraction form
    1,980.78/2,971.25 = 519.90/x
  3. Step 3: Cross multiply
    1,980.78x = 2,971.25 × 519.90
  4. Step 4: Simplify right side
    1,980.78x = 1,544,750.28
  5. Step 5: Solve for x
    x = 1,544,750.28/1,980.78
  6. Step 6: Final answer
    x = 779.87

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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.