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Finding the Fourth Proportional to 421.18, 577.51 and 379.56

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Solution

The fourth proportional to 421.18, 577.51 and 379.56 is: 520.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.18 : 577.51 = 379.56 : x
  2. Step 2: Convert to fraction form
    421.18/577.51 = 379.56/x
  3. Step 3: Cross multiply
    421.18x = 577.51 × 379.56
  4. Step 4: Simplify right side
    421.18x = 219,201.98
  5. Step 5: Solve for x
    x = 219,201.98/421.18
  6. Step 6: Final answer
    x = 520.45

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.