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Finding the Fourth Proportional to 646.78, 969.43 and 321.42

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Solution

The fourth proportional to 646.78, 969.43 and 321.42 is: 481.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.78 : 969.43 = 321.42 : x
  2. Step 2: Convert to fraction form
    646.78/969.43 = 321.42/x
  3. Step 3: Cross multiply
    646.78x = 969.43 × 321.42
  4. Step 4: Simplify right side
    646.78x = 311,594.19
  5. Step 5: Solve for x
    x = 311,594.19/646.78
  6. Step 6: Final answer
    x = 481.76

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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.