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Finding the Fourth Proportional to 389.05, 583.13 and 215.63

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Solution

The fourth proportional to 389.05, 583.13 and 215.63 is: 323.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.05 : 583.13 = 215.63 : x
  2. Step 2: Convert to fraction form
    389.05/583.13 = 215.63/x
  3. Step 3: Cross multiply
    389.05x = 583.13 × 215.63
  4. Step 4: Simplify right side
    389.05x = 125,740.32
  5. Step 5: Solve for x
    x = 125,740.32/389.05
  6. Step 6: Final answer
    x = 323.20

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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.