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Finding the Fourth Proportional to 642.45, 963.64 and 203.68

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Solution

The fourth proportional to 642.45, 963.64 and 203.68 is: 305.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.45 : 963.64 = 203.68 : x
  2. Step 2: Convert to fraction form
    642.45/963.64 = 203.68/x
  3. Step 3: Cross multiply
    642.45x = 963.64 × 203.68
  4. Step 4: Simplify right side
    642.45x = 196,274.20
  5. Step 5: Solve for x
    x = 196,274.20/642.45
  6. Step 6: Final answer
    x = 305.51

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Similar ratio
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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.