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Finding the Fourth Proportional to 455.22, 683.07 and 420.39

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Solution

The fourth proportional to 455.22, 683.07 and 420.39 is: 630.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    455.22 : 683.07 = 420.39 : x
  2. Step 2: Convert to fraction form
    455.22/683.07 = 420.39/x
  3. Step 3: Cross multiply
    455.22x = 683.07 × 420.39
  4. Step 4: Simplify right side
    455.22x = 287,155.80
  5. Step 5: Solve for x
    x = 287,155.80/455.22
  6. Step 6: Final answer
    x = 630.81

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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.