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Finding the Fourth Proportional to 637.31, 879.31 and 388.64

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Solution

The fourth proportional to 637.31, 879.31 and 388.64 is: 536.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.31 : 879.31 = 388.64 : x
  2. Step 2: Convert to fraction form
    637.31/879.31 = 388.64/x
  3. Step 3: Cross multiply
    637.31x = 879.31 × 388.64
  4. Step 4: Simplify right side
    637.31x = 341,735.04
  5. Step 5: Solve for x
    x = 341,735.04/637.31
  6. Step 6: Final answer
    x = 536.21

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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.