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Finding the Fourth Proportional to 800.70, 1,200.81 and 415.74

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Solution

The fourth proportional to 800.70, 1,200.81 and 415.74 is: 623.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.70 : 1,200.81 = 415.74 : x
  2. Step 2: Convert to fraction form
    800.70/1,200.81 = 415.74/x
  3. Step 3: Cross multiply
    800.70x = 1,200.81 × 415.74
  4. Step 4: Simplify right side
    800.70x = 499,224.75
  5. Step 5: Solve for x
    x = 499,224.75/800.70
  6. Step 6: Final answer
    x = 623.49

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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.