Home / 728.20-1,091.10-605.80

Finding the Fourth Proportional to 728.20, 1,091.10 and 605.80

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Solution

The fourth proportional to 728.20, 1,091.10 and 605.80 is: 907.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.20 : 1,091.10 = 605.80 : x
  2. Step 2: Convert to fraction form
    728.20/1,091.10 = 605.80/x
  3. Step 3: Cross multiply
    728.20x = 1,091.10 × 605.80
  4. Step 4: Simplify right side
    728.20x = 660,988.38
  5. Step 5: Solve for x
    x = 660,988.38/728.20
  6. Step 6: Final answer
    x = 907.70

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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.