Home / 1,081.28-1,621.93-311.78

Finding the Fourth Proportional to 1,081.28, 1,621.93 and 311.78

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Solution

The fourth proportional to 1,081.28, 1,621.93 and 311.78 is: 467.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,081.28 : 1,621.93 = 311.78 : x
  2. Step 2: Convert to fraction form
    1,081.28/1,621.93 = 311.78/x
  3. Step 3: Cross multiply
    1,081.28x = 1,621.93 × 311.78
  4. Step 4: Simplify right side
    1,081.28x = 505,685.34
  5. Step 5: Solve for x
    x = 505,685.34/1,081.28
  6. Step 6: Final answer
    x = 467.67

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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.