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Finding the Fourth Proportional to 611.43, 842.31 and 487.05

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Solution

The fourth proportional to 611.43, 842.31 and 487.05 is: 670.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.43 : 842.31 = 487.05 : x
  2. Step 2: Convert to fraction form
    611.43/842.31 = 487.05/x
  3. Step 3: Cross multiply
    611.43x = 842.31 × 487.05
  4. Step 4: Simplify right side
    611.43x = 410,247.09
  5. Step 5: Solve for x
    x = 410,247.09/611.43
  6. Step 6: Final answer
    x = 670.96

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.