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Finding the Fourth Proportional to 680.70, 939.09 and 415.05

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Solution

The fourth proportional to 680.70, 939.09 and 415.05 is: 572.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.70 : 939.09 = 415.05 : x
  2. Step 2: Convert to fraction form
    680.70/939.09 = 415.05/x
  3. Step 3: Cross multiply
    680.70x = 939.09 × 415.05
  4. Step 4: Simplify right side
    680.70x = 389,769.30
  5. Step 5: Solve for x
    x = 389,769.30/680.70
  6. Step 6: Final answer
    x = 572.60

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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.