Home / 1,989.20-2,981.22-817.88

Finding the Fourth Proportional to 1,989.20, 2,981.22 and 817.88

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Solution

The fourth proportional to 1,989.20, 2,981.22 and 817.88 is: 1,225.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,989.20 : 2,981.22 = 817.88 : x
  2. Step 2: Convert to fraction form
    1,989.20/2,981.22 = 817.88/x
  3. Step 3: Cross multiply
    1,989.20x = 2,981.22 × 817.88
  4. Step 4: Simplify right side
    1,989.20x = 2,438,280.21
  5. Step 5: Solve for x
    x = 2,438,280.21/1,989.20
  6. Step 6: Final answer
    x = 1,225.76

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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.