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Finding the Fourth Proportional to 680.90, 939.30 and 484.52

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Solution

The fourth proportional to 680.90, 939.30 and 484.52 is: 668.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.90 : 939.30 = 484.52 : x
  2. Step 2: Convert to fraction form
    680.90/939.30 = 484.52/x
  3. Step 3: Cross multiply
    680.90x = 939.30 × 484.52
  4. Step 4: Simplify right side
    680.90x = 455,109.64
  5. Step 5: Solve for x
    x = 455,109.64/680.90
  6. Step 6: Final answer
    x = 668.39

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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.