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Finding the Fourth Proportional to 815.00, 1,221.35 and 327.49

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Solution

The fourth proportional to 815.00, 1,221.35 and 327.49 is: 490.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    815.00 : 1,221.35 = 327.49 : x
  2. Step 2: Convert to fraction form
    815.00/1,221.35 = 327.49/x
  3. Step 3: Cross multiply
    815.00x = 1,221.35 × 327.49
  4. Step 4: Simplify right side
    815.00x = 399,975.22
  5. Step 5: Solve for x
    x = 399,975.22/815.00
  6. Step 6: Final answer
    x = 490.77

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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.