Home / 1,289.45-1,778.35-869.25

Finding the Fourth Proportional to 1,289.45, 1,778.35 and 869.25

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Solution

The fourth proportional to 1,289.45, 1,778.35 and 869.25 is: 1,198.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.45 : 1,778.35 = 869.25 : x
  2. Step 2: Convert to fraction form
    1,289.45/1,778.35 = 869.25/x
  3. Step 3: Cross multiply
    1,289.45x = 1,778.35 × 869.25
  4. Step 4: Simplify right side
    1,289.45x = 1,545,830.84
  5. Step 5: Solve for x
    x = 1,545,830.84/1,289.45
  6. Step 6: Final answer
    x = 1,198.83

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.