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Finding the Fourth Proportional to 618.87, 928.42 and 208.05

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Solution

The fourth proportional to 618.87, 928.42 and 208.05 is: 312.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.87 : 928.42 = 208.05 : x
  2. Step 2: Convert to fraction form
    618.87/928.42 = 208.05/x
  3. Step 3: Cross multiply
    618.87x = 928.42 × 208.05
  4. Step 4: Simplify right side
    618.87x = 193,157.78
  5. Step 5: Solve for x
    x = 193,157.78/618.87
  6. Step 6: Final answer
    x = 312.11

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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.