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Finding the Fourth Proportional to 680.20, 938.72 and 385.44

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Solution

The fourth proportional to 680.20, 938.72 and 385.44 is: 531.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.20 : 938.72 = 385.44 : x
  2. Step 2: Convert to fraction form
    680.20/938.72 = 385.44/x
  3. Step 3: Cross multiply
    680.20x = 938.72 × 385.44
  4. Step 4: Simplify right side
    680.20x = 361,820.24
  5. Step 5: Solve for x
    x = 361,820.24/680.20
  6. Step 6: Final answer
    x = 531.93

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1.5x scale

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.