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Finding the Fourth Proportional to 1,385.39, 2,078.08 and 728.37

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Solution

The fourth proportional to 1,385.39, 2,078.08 and 728.37 is: 1,092.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,385.39 : 2,078.08 = 728.37 : x
  2. Step 2: Convert to fraction form
    1,385.39/2,078.08 = 728.37/x
  3. Step 3: Cross multiply
    1,385.39x = 2,078.08 × 728.37
  4. Step 4: Simplify right side
    1,385.39x = 1,513,611.13
  5. Step 5: Solve for x
    x = 1,513,611.13/1,385.39
  6. Step 6: Final answer
    x = 1,092.55

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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.