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Finding the Fourth Proportional to 427.95, 642.02 and 208.62

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Solution

The fourth proportional to 427.95, 642.02 and 208.62 is: 312.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.95 : 642.02 = 208.62 : x
  2. Step 2: Convert to fraction form
    427.95/642.02 = 208.62/x
  3. Step 3: Cross multiply
    427.95x = 642.02 × 208.62
  4. Step 4: Simplify right side
    427.95x = 133,937.17
  5. Step 5: Solve for x
    x = 133,937.17/427.95
  6. Step 6: Final answer
    x = 312.97

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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.