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Finding the Fourth Proportional to 613.31, 919.86 and 279.68

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Solution

The fourth proportional to 613.31, 919.86 and 279.68 is: 419.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.31 : 919.86 = 279.68 : x
  2. Step 2: Convert to fraction form
    613.31/919.86 = 279.68/x
  3. Step 3: Cross multiply
    613.31x = 919.86 × 279.68
  4. Step 4: Simplify right side
    613.31x = 257,266.44
  5. Step 5: Solve for x
    x = 257,266.44/613.31
  6. Step 6: Final answer
    x = 419.47

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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.