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Finding the Fourth Proportional to 520.20, 778.68 and 389.48

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Solution

The fourth proportional to 520.20, 778.68 and 389.48 is: 583.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.20 : 778.68 = 389.48 : x
  2. Step 2: Convert to fraction form
    520.20/778.68 = 389.48/x
  3. Step 3: Cross multiply
    520.20x = 778.68 × 389.48
  4. Step 4: Simplify right side
    520.20x = 303,276.39
  5. Step 5: Solve for x
    x = 303,276.39/520.20
  6. Step 6: Final answer
    x = 583.00

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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.