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Finding the Fourth Proportional to 679.20, 937.20 and 380.40

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Solution

The fourth proportional to 679.20, 937.20 and 380.40 is: 524.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.20 : 937.20 = 380.40 : x
  2. Step 2: Convert to fraction form
    679.20/937.20 = 380.40/x
  3. Step 3: Cross multiply
    679.20x = 937.20 × 380.40
  4. Step 4: Simplify right side
    679.20x = 356,510.88
  5. Step 5: Solve for x
    x = 356,510.88/679.20
  6. Step 6: Final answer
    x = 524.90

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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.