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Finding the Fourth Proportional to 646.85, 892.85 and 398.53

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Solution

The fourth proportional to 646.85, 892.85 and 398.53 is: 550.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.85 : 892.85 = 398.53 : x
  2. Step 2: Convert to fraction form
    646.85/892.85 = 398.53/x
  3. Step 3: Cross multiply
    646.85x = 892.85 × 398.53
  4. Step 4: Simplify right side
    646.85x = 355,821.05
  5. Step 5: Solve for x
    x = 355,821.05/646.85
  6. Step 6: Final answer
    x = 550.08

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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.