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Finding the Fourth Proportional to 613.80, 919.90 and 442.60

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Solution

The fourth proportional to 613.80, 919.90 and 442.60 is: 663.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.80 : 919.90 = 442.60 : x
  2. Step 2: Convert to fraction form
    613.80/919.90 = 442.60/x
  3. Step 3: Cross multiply
    613.80x = 919.90 × 442.60
  4. Step 4: Simplify right side
    613.80x = 407,147.74
  5. Step 5: Solve for x
    x = 407,147.74/613.80
  6. Step 6: Final answer
    x = 663.32

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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.