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Finding the Fourth Proportional to 326.80, 490.20 and 305.20

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Solution

The fourth proportional to 326.80, 490.20 and 305.20 is: 457.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    326.80 : 490.20 = 305.20 : x
  2. Step 2: Convert to fraction form
    326.80/490.20 = 305.20/x
  3. Step 3: Cross multiply
    326.80x = 490.20 × 305.20
  4. Step 4: Simplify right side
    326.80x = 149,609.04
  5. Step 5: Solve for x
    x = 149,609.04/326.80
  6. Step 6: Final answer
    x = 457.80

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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.