Home / 2,085-3,121.28-1,260.78

Finding the Fourth Proportional to 2,085, 3,121.28 and 1,260.78

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Solution

The fourth proportional to 2,085, 3,121.28 and 1,260.78 is: 1,887.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,085 : 3,121.28 = 1,260.78 : x
  2. Step 2: Convert to fraction form
    2,085/3,121.28 = 1,260.78/x
  3. Step 3: Cross multiply
    2,085x = 3,121.28 × 1,260.78
  4. Step 4: Simplify right side
    2,085x = 3,935,247.40
  5. Step 5: Solve for x
    x = 3,935,247.40/2,085
  6. Step 6: Final answer
    x = 1,887.41

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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.