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Finding the Fourth Proportional to 643.19, 963.19 and 613.58

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Solution

The fourth proportional to 643.19, 963.19 and 613.58 is: 918.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.19 : 963.19 = 613.58 : x
  2. Step 2: Convert to fraction form
    643.19/963.19 = 613.58/x
  3. Step 3: Cross multiply
    643.19x = 963.19 × 613.58
  4. Step 4: Simplify right side
    643.19x = 590,990.07
  5. Step 5: Solve for x
    x = 590,990.07/643.19
  6. Step 6: Final answer
    x = 918.84

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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.