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Finding the Fourth Proportional to 643.48, 965.26 and 399.50

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Solution

The fourth proportional to 643.48, 965.26 and 399.50 is: 599.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.48 : 965.26 = 399.50 : x
  2. Step 2: Convert to fraction form
    643.48/965.26 = 399.50/x
  3. Step 3: Cross multiply
    643.48x = 965.26 × 399.50
  4. Step 4: Simplify right side
    643.48x = 385,620.66
  5. Step 5: Solve for x
    x = 385,620.66/643.48
  6. Step 6: Final answer
    x = 599.28

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.