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Finding the Fourth Proportional to 666.11, 999.12 and 255.21

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Solution

The fourth proportional to 666.11, 999.12 and 255.21 is: 382.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.11 : 999.12 = 255.21 : x
  2. Step 2: Convert to fraction form
    666.11/999.12 = 255.21/x
  3. Step 3: Cross multiply
    666.11x = 999.12 × 255.21
  4. Step 4: Simplify right side
    666.11x = 254,985.42
  5. Step 5: Solve for x
    x = 254,985.42/666.11
  6. Step 6: Final answer
    x = 382.80

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1.5x scale

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.