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Finding the Fourth Proportional to 643.19, 887.63 and 394.37

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Solution

The fourth proportional to 643.19, 887.63 and 394.37 is: 544.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.19 : 887.63 = 394.37 : x
  2. Step 2: Convert to fraction form
    643.19/887.63 = 394.37/x
  3. Step 3: Cross multiply
    643.19x = 887.63 × 394.37
  4. Step 4: Simplify right side
    643.19x = 350,053.23
  5. Step 5: Solve for x
    x = 350,053.23/643.19
  6. Step 6: Final answer
    x = 544.24

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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.