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Finding the Fourth Proportional to 677.38, 1,015.80 and 389.02

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Solution

The fourth proportional to 677.38, 1,015.80 and 389.02 is: 583.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    677.38 : 1,015.80 = 389.02 : x
  2. Step 2: Convert to fraction form
    677.38/1,015.80 = 389.02/x
  3. Step 3: Cross multiply
    677.38x = 1,015.80 × 389.02
  4. Step 4: Simplify right side
    677.38x = 395,166.52
  5. Step 5: Solve for x
    x = 395,166.52/677.38
  6. Step 6: Final answer
    x = 583.37

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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.