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Finding the Fourth Proportional to 800.28, 1,200.40 and 540.40

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Solution

The fourth proportional to 800.28, 1,200.40 and 540.40 is: 810.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.28 : 1,200.40 = 540.40 : x
  2. Step 2: Convert to fraction form
    800.28/1,200.40 = 540.40/x
  3. Step 3: Cross multiply
    800.28x = 1,200.40 × 540.40
  4. Step 4: Simplify right side
    800.28x = 648,696.16
  5. Step 5: Solve for x
    x = 648,696.16/800.28
  6. Step 6: Final answer
    x = 810.59

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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.