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Finding the Fourth Proportional to 855.30, 1,280.21 and 577.15

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Solution

The fourth proportional to 855.30, 1,280.21 and 577.15 is: 863.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    855.30 : 1,280.21 = 577.15 : x
  2. Step 2: Convert to fraction form
    855.30/1,280.21 = 577.15/x
  3. Step 3: Cross multiply
    855.30x = 1,280.21 × 577.15
  4. Step 4: Simplify right side
    855.30x = 738,873.20
  5. Step 5: Solve for x
    x = 738,873.20/855.30
  6. Step 6: Final answer
    x = 863.88

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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.