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Finding the Fourth Proportional to 680.03, 931.38 and 640.12

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Solution

The fourth proportional to 680.03, 931.38 and 640.12 is: 876.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.03 : 931.38 = 640.12 : x
  2. Step 2: Convert to fraction form
    680.03/931.38 = 640.12/x
  3. Step 3: Cross multiply
    680.03x = 931.38 × 640.12
  4. Step 4: Simplify right side
    680.03x = 596,190.31
  5. Step 5: Solve for x
    x = 596,190.31/680.03
  6. Step 6: Final answer
    x = 876.72

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.