Home / 1,289.55-1,935-1,219.85

Finding the Fourth Proportional to 1,289.55, 1,935 and 1,219.85

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Solution

The fourth proportional to 1,289.55, 1,935 and 1,219.85 is: 1,830.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.55 : 1,935 = 1,219.85 : x
  2. Step 2: Convert to fraction form
    1,289.55/1,935 = 1,219.85/x
  3. Step 3: Cross multiply
    1,289.55x = 1,935 × 1,219.85
  4. Step 4: Simplify right side
    1,289.55x = 2,360,400.08
  5. Step 5: Solve for x
    x = 2,360,400.08/1,289.55
  6. Step 6: Final answer
    x = 1,830.41

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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.