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Finding the Fourth Proportional to 679.00, 1,015.39 and 505.79

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Solution

The fourth proportional to 679.00, 1,015.39 and 505.79 is: 756.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.00 : 1,015.39 = 505.79 : x
  2. Step 2: Convert to fraction form
    679.00/1,015.39 = 505.79/x
  3. Step 3: Cross multiply
    679.00x = 1,015.39 × 505.79
  4. Step 4: Simplify right side
    679.00x = 513,567.77
  5. Step 5: Solve for x
    x = 513,567.77/679.00
  6. Step 6: Final answer
    x = 756.36

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.