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Finding the Fourth Proportional to 679.88, 938.18 and 385.12

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Solution

The fourth proportional to 679.88, 938.18 and 385.12 is: 531.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.88 : 938.18 = 385.12 : x
  2. Step 2: Convert to fraction form
    679.88/938.18 = 385.12/x
  3. Step 3: Cross multiply
    679.88x = 938.18 × 385.12
  4. Step 4: Simplify right side
    679.88x = 361,311.88
  5. Step 5: Solve for x
    x = 361,311.88/679.88
  6. Step 6: Final answer
    x = 531.43

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.