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Finding the Fourth Proportional to 680.70, 939.15 and 605.10

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Solution

The fourth proportional to 680.70, 939.15 and 605.10 is: 834.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.70 : 939.15 = 605.10 : x
  2. Step 2: Convert to fraction form
    680.70/939.15 = 605.10/x
  3. Step 3: Cross multiply
    680.70x = 939.15 × 605.10
  4. Step 4: Simplify right side
    680.70x = 568,279.67
  5. Step 5: Solve for x
    x = 568,279.67/680.70
  6. Step 6: Final answer
    x = 834.85

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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.