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Finding the Fourth Proportional to 427.50, 643.83 and 379.35

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Solution

The fourth proportional to 427.50, 643.83 and 379.35 is: 571.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.50 : 643.83 = 379.35 : x
  2. Step 2: Convert to fraction form
    427.50/643.83 = 379.35/x
  3. Step 3: Cross multiply
    427.50x = 643.83 × 379.35
  4. Step 4: Simplify right side
    427.50x = 244,236.91
  5. Step 5: Solve for x
    x = 244,236.91/427.50
  6. Step 6: Final answer
    x = 571.31

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.