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Finding the Fourth Proportional to 1,321.91, 1,982.82 and 628.91

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Solution

The fourth proportional to 1,321.91, 1,982.82 and 628.91 is: 943.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.91 : 1,982.82 = 628.91 : x
  2. Step 2: Convert to fraction form
    1,321.91/1,982.82 = 628.91/x
  3. Step 3: Cross multiply
    1,321.91x = 1,982.82 × 628.91
  4. Step 4: Simplify right side
    1,321.91x = 1,247,015.33
  5. Step 5: Solve for x
    x = 1,247,015.33/1,321.91
  6. Step 6: Final answer
    x = 943.34

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1.5x scale

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.