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Finding the Fourth Proportional to 637.31, 879.57 and 388.66

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Solution

The fourth proportional to 637.31, 879.57 and 388.66 is: 536.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.31 : 879.57 = 388.66 : x
  2. Step 2: Convert to fraction form
    637.31/879.57 = 388.66/x
  3. Step 3: Cross multiply
    637.31x = 879.57 × 388.66
  4. Step 4: Simplify right side
    637.31x = 341,853.68
  5. Step 5: Solve for x
    x = 341,853.68/637.31
  6. Step 6: Final answer
    x = 536.40

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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.