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Finding the Fourth Proportional to 679.61, 938.40 and 443.72

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Solution

The fourth proportional to 679.61, 938.40 and 443.72 is: 612.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.61 : 938.40 = 443.72 : x
  2. Step 2: Convert to fraction form
    679.61/938.40 = 443.72/x
  3. Step 3: Cross multiply
    679.61x = 938.40 × 443.72
  4. Step 4: Simplify right side
    679.61x = 416,386.85
  5. Step 5: Solve for x
    x = 416,386.85/679.61
  6. Step 6: Final answer
    x = 612.68

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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.