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Finding the Fourth Proportional to 666.21, 998.85 and 319.62

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Solution

The fourth proportional to 666.21, 998.85 and 319.62 is: 479.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.21 : 998.85 = 319.62 : x
  2. Step 2: Convert to fraction form
    666.21/998.85 = 319.62/x
  3. Step 3: Cross multiply
    666.21x = 998.85 × 319.62
  4. Step 4: Simplify right side
    666.21x = 319,252.44
  5. Step 5: Solve for x
    x = 319,252.44/666.21
  6. Step 6: Final answer
    x = 479.21

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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.