Home / 1,981.78-2,969.79-1,111.66

Finding the Fourth Proportional to 1,981.78, 2,969.79 and 1,111.66

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Solution

The fourth proportional to 1,981.78, 2,969.79 and 1,111.66 is: 1,665.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,981.78 : 2,969.79 = 1,111.66 : x
  2. Step 2: Convert to fraction form
    1,981.78/2,969.79 = 1,111.66/x
  3. Step 3: Cross multiply
    1,981.78x = 2,969.79 × 1,111.66
  4. Step 4: Simplify right side
    1,981.78x = 3,301,396.75
  5. Step 5: Solve for x
    x = 3,301,396.75/1,981.78
  6. Step 6: Final answer
    x = 1,665.87

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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.