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Finding the Fourth Proportional to 830.20, 1,245.40 and 274.69

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Solution

The fourth proportional to 830.20, 1,245.40 and 274.69 is: 412.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.20 : 1,245.40 = 274.69 : x
  2. Step 2: Convert to fraction form
    830.20/1,245.40 = 274.69/x
  3. Step 3: Cross multiply
    830.20x = 1,245.40 × 274.69
  4. Step 4: Simplify right side
    830.20x = 342,100.57
  5. Step 5: Solve for x
    x = 342,100.57/830.20
  6. Step 6: Final answer
    x = 412.07

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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.