Home / 1,120.28-1,680.57-389.75

Finding the Fourth Proportional to 1,120.28, 1,680.57 and 389.75

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Solution

The fourth proportional to 1,120.28, 1,680.57 and 389.75 is: 584.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,120.28 : 1,680.57 = 389.75 : x
  2. Step 2: Convert to fraction form
    1,120.28/1,680.57 = 389.75/x
  3. Step 3: Cross multiply
    1,120.28x = 1,680.57 × 389.75
  4. Step 4: Simplify right side
    1,120.28x = 654,993.75
  5. Step 5: Solve for x
    x = 654,993.75/1,120.28
  6. Step 6: Final answer
    x = 584.67

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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.