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Finding the Fourth Proportional to 820.10, 1,228.35 and 636.05

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Solution

The fourth proportional to 820.10, 1,228.35 and 636.05 is: 952.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.10 : 1,228.35 = 636.05 : x
  2. Step 2: Convert to fraction form
    820.10/1,228.35 = 636.05/x
  3. Step 3: Cross multiply
    820.10x = 1,228.35 × 636.05
  4. Step 4: Simplify right side
    820.10x = 781,292.02
  5. Step 5: Solve for x
    x = 781,292.02/820.10
  6. Step 6: Final answer
    x = 952.68

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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.