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Finding the Fourth Proportional to 611.45, 842.69 and 445.40

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Solution

The fourth proportional to 611.45, 842.69 and 445.40 is: 613.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.45 : 842.69 = 445.40 : x
  2. Step 2: Convert to fraction form
    611.45/842.69 = 445.40/x
  3. Step 3: Cross multiply
    611.45x = 842.69 × 445.40
  4. Step 4: Simplify right side
    611.45x = 375,331.03
  5. Step 5: Solve for x
    x = 375,331.03/611.45
  6. Step 6: Final answer
    x = 613.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.