Home / 2,139.13-3,206.80-840.30

Finding the Fourth Proportional to 2,139.13, 3,206.80 and 840.30

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Solution

The fourth proportional to 2,139.13, 3,206.80 and 840.30 is: 1,259.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,139.13 : 3,206.80 = 840.30 : x
  2. Step 2: Convert to fraction form
    2,139.13/3,206.80 = 840.30/x
  3. Step 3: Cross multiply
    2,139.13x = 3,206.80 × 840.30
  4. Step 4: Simplify right side
    2,139.13x = 2,694,674.04
  5. Step 5: Solve for x
    x = 2,694,674.04/2,139.13
  6. Step 6: Final answer
    x = 1,259.71

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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.