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Finding the Fourth Proportional to 679.19, 939.20 and 550.40

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Solution

The fourth proportional to 679.19, 939.20 and 550.40 is: 761.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.19 : 939.20 = 550.40 : x
  2. Step 2: Convert to fraction form
    679.19/939.20 = 550.40/x
  3. Step 3: Cross multiply
    679.19x = 939.20 × 550.40
  4. Step 4: Simplify right side
    679.19x = 516,928.23
  5. Step 5: Solve for x
    x = 516,928.23/679.19
  6. Step 6: Final answer
    x = 761.10

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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.