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Finding the Fourth Proportional to 680.38, 1,020.35 and 218.05

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Solution

The fourth proportional to 680.38, 1,020.35 and 218.05 is: 327.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.38 : 1,020.35 = 218.05 : x
  2. Step 2: Convert to fraction form
    680.38/1,020.35 = 218.05/x
  3. Step 3: Cross multiply
    680.38x = 1,020.35 × 218.05
  4. Step 4: Simplify right side
    680.38x = 222,485.31
  5. Step 5: Solve for x
    x = 222,485.31/680.38
  6. Step 6: Final answer
    x = 327.00

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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.