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Finding the Fourth Proportional to 643.60, 888.14 and 394.88

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Solution

The fourth proportional to 643.60, 888.14 and 394.88 is: 544.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.60 : 888.14 = 394.88 : x
  2. Step 2: Convert to fraction form
    643.60/888.14 = 394.88/x
  3. Step 3: Cross multiply
    643.60x = 888.14 × 394.88
  4. Step 4: Simplify right side
    643.60x = 350,708.72
  5. Step 5: Solve for x
    x = 350,708.72/643.60
  6. Step 6: Final answer
    x = 544.92

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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.