Home / 1,211.28-1,817.12-480.80

Finding the Fourth Proportional to 1,211.28, 1,817.12 and 480.80

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Solution

The fourth proportional to 1,211.28, 1,817.12 and 480.80 is: 721.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.28 : 1,817.12 = 480.80 : x
  2. Step 2: Convert to fraction form
    1,211.28/1,817.12 = 480.80/x
  3. Step 3: Cross multiply
    1,211.28x = 1,817.12 × 480.80
  4. Step 4: Simplify right side
    1,211.28x = 873,671.30
  5. Step 5: Solve for x
    x = 873,671.30/1,211.28
  6. Step 6: Final answer
    x = 721.28

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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.