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Finding the Fourth Proportional to 721.90, 997.14 and 680.86

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Solution

The fourth proportional to 721.90, 997.14 and 680.86 is: 940.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.90 : 997.14 = 680.86 : x
  2. Step 2: Convert to fraction form
    721.90/997.14 = 680.86/x
  3. Step 3: Cross multiply
    721.90x = 997.14 × 680.86
  4. Step 4: Simplify right side
    721.90x = 678,912.74
  5. Step 5: Solve for x
    x = 678,912.74/721.90
  6. Step 6: Final answer
    x = 940.45

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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.