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Finding the Fourth Proportional to 643.35, 887.76 and 394.74

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Solution

The fourth proportional to 643.35, 887.76 and 394.74 is: 544.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.35 : 887.76 = 394.74 : x
  2. Step 2: Convert to fraction form
    643.35/887.76 = 394.74/x
  3. Step 3: Cross multiply
    643.35x = 887.76 × 394.74
  4. Step 4: Simplify right side
    643.35x = 350,434.38
  5. Step 5: Solve for x
    x = 350,434.38/643.35
  6. Step 6: Final answer
    x = 544.70

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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.