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Finding the Fourth Proportional to 789.96, 1,089.36 and 615

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Solution

The fourth proportional to 789.96, 1,089.36 and 615 is: 848.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    789.96 : 1,089.36 = 615 : x
  2. Step 2: Convert to fraction form
    789.96/1,089.36 = 615/x
  3. Step 3: Cross multiply
    789.96x = 1,089.36 × 615
  4. Step 4: Simplify right side
    789.96x = 669,956.40
  5. Step 5: Solve for x
    x = 669,956.40/789.96
  6. Step 6: Final answer
    x = 848.09

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.