Home / 911.20-1,366.80-720.16

Finding the Fourth Proportional to 911.20, 1,366.80 and 720.16

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Solution

The fourth proportional to 911.20, 1,366.80 and 720.16 is: 1,080.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    911.20 : 1,366.80 = 720.16 : x
  2. Step 2: Convert to fraction form
    911.20/1,366.80 = 720.16/x
  3. Step 3: Cross multiply
    911.20x = 1,366.80 × 720.16
  4. Step 4: Simplify right side
    911.20x = 984,314.69
  5. Step 5: Solve for x
    x = 984,314.69/911.20
  6. Step 6: Final answer
    x = 1,080.24

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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.