Home / 1,989.92-2,984.38-1,285

Finding the Fourth Proportional to 1,989.92, 2,984.38 and 1,285

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Solution

The fourth proportional to 1,989.92, 2,984.38 and 1,285 is: 1,927.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,989.92 : 2,984.38 = 1,285 : x
  2. Step 2: Convert to fraction form
    1,989.92/2,984.38 = 1,285/x
  3. Step 3: Cross multiply
    1,989.92x = 2,984.38 × 1,285
  4. Step 4: Simplify right side
    1,989.92x = 3,834,928.30
  5. Step 5: Solve for x
    x = 3,834,928.30/1,989.92
  6. Step 6: Final answer
    x = 1,927.18

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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.