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Finding the Fourth Proportional to 643.19, 964.81 and 369.15

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Solution

The fourth proportional to 643.19, 964.81 and 369.15 is: 553.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.19 : 964.81 = 369.15 : x
  2. Step 2: Convert to fraction form
    643.19/964.81 = 369.15/x
  3. Step 3: Cross multiply
    643.19x = 964.81 × 369.15
  4. Step 4: Simplify right side
    643.19x = 356,159.61
  5. Step 5: Solve for x
    x = 356,159.61/643.19
  6. Step 6: Final answer
    x = 553.74

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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.