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Finding the Fourth Proportional to 664.80, 913.57 and 634.31

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Solution

The fourth proportional to 664.80, 913.57 and 634.31 is: 871.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.80 : 913.57 = 634.31 : x
  2. Step 2: Convert to fraction form
    664.80/913.57 = 634.31/x
  3. Step 3: Cross multiply
    664.80x = 913.57 × 634.31
  4. Step 4: Simplify right side
    664.80x = 579,490.00
  5. Step 5: Solve for x
    x = 579,490.00/664.80
  6. Step 6: Final answer
    x = 871.67

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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.