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Finding the Fourth Proportional to 618.79, 928.21 and 208.07

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Solution

The fourth proportional to 618.79, 928.21 and 208.07 is: 312.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.79 : 928.21 = 208.07 : x
  2. Step 2: Convert to fraction form
    618.79/928.21 = 208.07/x
  3. Step 3: Cross multiply
    618.79x = 928.21 × 208.07
  4. Step 4: Simplify right side
    618.79x = 193,131.36
  5. Step 5: Solve for x
    x = 193,131.36/618.79
  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.