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Finding the Fourth Proportional to 427.41, 640.31 and 389.34

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Solution

The fourth proportional to 427.41, 640.31 and 389.34 is: 583.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.41 : 640.31 = 389.34 : x
  2. Step 2: Convert to fraction form
    427.41/640.31 = 389.34/x
  3. Step 3: Cross multiply
    427.41x = 640.31 × 389.34
  4. Step 4: Simplify right side
    427.41x = 249,296.35
  5. Step 5: Solve for x
    x = 249,296.35/427.41
  6. Step 6: Final answer
    x = 583.27

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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.