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Finding the Fourth Proportional to 1,280.88, 1,921.32 and 871.02

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Solution

The fourth proportional to 1,280.88, 1,921.32 and 871.02 is: 1,306.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.88 : 1,921.32 = 871.02 : x
  2. Step 2: Convert to fraction form
    1,280.88/1,921.32 = 871.02/x
  3. Step 3: Cross multiply
    1,280.88x = 1,921.32 × 871.02
  4. Step 4: Simplify right side
    1,280.88x = 1,673,508.15
  5. Step 5: Solve for x
    x = 1,673,508.15/1,280.88
  6. Step 6: Final answer
    x = 1,306.53

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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.