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Finding the Fourth Proportional to 643.08, 963.96 and 258.60

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Solution

The fourth proportional to 643.08, 963.96 and 258.60 is: 387.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.08 : 963.96 = 258.60 : x
  2. Step 2: Convert to fraction form
    643.08/963.96 = 258.60/x
  3. Step 3: Cross multiply
    643.08x = 963.96 × 258.60
  4. Step 4: Simplify right side
    643.08x = 249,280.06
  5. Step 5: Solve for x
    x = 249,280.06/643.08
  6. Step 6: Final answer
    x = 387.63

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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.