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Finding the Fourth Proportional to 679.16, 936.88 and 399.30

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Solution

The fourth proportional to 679.16, 936.88 and 399.30 is: 550.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.16 : 936.88 = 399.30 : x
  2. Step 2: Convert to fraction form
    679.16/936.88 = 399.30/x
  3. Step 3: Cross multiply
    679.16x = 936.88 × 399.30
  4. Step 4: Simplify right side
    679.16x = 374,096.18
  5. Step 5: Solve for x
    x = 374,096.18/679.16
  6. Step 6: Final answer
    x = 550.82

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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.