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Finding the Fourth Proportional to 798.80, 1,198.80 and 305.64

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Solution

The fourth proportional to 798.80, 1,198.80 and 305.64 is: 458.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    798.80 : 1,198.80 = 305.64 : x
  2. Step 2: Convert to fraction form
    798.80/1,198.80 = 305.64/x
  3. Step 3: Cross multiply
    798.80x = 1,198.80 × 305.64
  4. Step 4: Simplify right side
    798.80x = 366,401.23
  5. Step 5: Solve for x
    x = 366,401.23/798.80
  6. Step 6: Final answer
    x = 458.69

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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.