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Finding the Fourth Proportional to 666.75, 999.94 and 342.21

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Solution

The fourth proportional to 666.75, 999.94 and 342.21 is: 513.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.75 : 999.94 = 342.21 : x
  2. Step 2: Convert to fraction form
    666.75/999.94 = 342.21/x
  3. Step 3: Cross multiply
    666.75x = 999.94 × 342.21
  4. Step 4: Simplify right side
    666.75x = 342,189.47
  5. Step 5: Solve for x
    x = 342,189.47/666.75
  6. Step 6: Final answer
    x = 513.22

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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.