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Finding the Fourth Proportional to 804.10, 1,206.15 and 419.30

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Solution

The fourth proportional to 804.10, 1,206.15 and 419.30 is: 628.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    804.10 : 1,206.15 = 419.30 : x
  2. Step 2: Convert to fraction form
    804.10/1,206.15 = 419.30/x
  3. Step 3: Cross multiply
    804.10x = 1,206.15 × 419.30
  4. Step 4: Simplify right side
    804.10x = 505,738.70
  5. Step 5: Solve for x
    x = 505,738.70/804.10
  6. Step 6: Final answer
    x = 628.95

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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.