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Finding the Fourth Proportional to 642.17, 963.23 and 209.30

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Solution

The fourth proportional to 642.17, 963.23 and 209.30 is: 313.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.17 : 963.23 = 209.30 : x
  2. Step 2: Convert to fraction form
    642.17/963.23 = 209.30/x
  3. Step 3: Cross multiply
    642.17x = 963.23 × 209.30
  4. Step 4: Simplify right side
    642.17x = 201,598.18
  5. Step 5: Solve for x
    x = 201,598.18/642.17
  6. Step 6: Final answer
    x = 313.93

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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.