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Finding the Fourth Proportional to 643.02, 887.02 and 394.39

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Solution

The fourth proportional to 643.02, 887.02 and 394.39 is: 544.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.02 : 887.02 = 394.39 : x
  2. Step 2: Convert to fraction form
    643.02/887.02 = 394.39/x
  3. Step 3: Cross multiply
    643.02x = 887.02 × 394.39
  4. Step 4: Simplify right side
    643.02x = 349,831.82
  5. Step 5: Solve for x
    x = 349,831.82/643.02
  6. Step 6: Final answer
    x = 544.05

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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.