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Finding the Fourth Proportional to 679.62, 938.10 and 620.15

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Solution

The fourth proportional to 679.62, 938.10 and 620.15 is: 856.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.62 : 938.10 = 620.15 : x
  2. Step 2: Convert to fraction form
    679.62/938.10 = 620.15/x
  3. Step 3: Cross multiply
    679.62x = 938.10 × 620.15
  4. Step 4: Simplify right side
    679.62x = 581,767.40
  5. Step 5: Solve for x
    x = 581,767.40/679.62
  6. Step 6: Final answer
    x = 856.02

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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.