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Finding the Fourth Proportional to 389.10, 583.64 and 115.19

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Solution

The fourth proportional to 389.10, 583.64 and 115.19 is: 172.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.10 : 583.64 = 115.19 : x
  2. Step 2: Convert to fraction form
    389.10/583.64 = 115.19/x
  3. Step 3: Cross multiply
    389.10x = 583.64 × 115.19
  4. Step 4: Simplify right side
    389.10x = 67,229.49
  5. Step 5: Solve for x
    x = 67,229.49/389.10
  6. Step 6: Final answer
    x = 172.78

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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.