Home / 2,811-4,218.39-1,686.18

Finding the Fourth Proportional to 2,811, 4,218.39 and 1,686.18

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Solution

The fourth proportional to 2,811, 4,218.39 and 1,686.18 is: 2,530.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,811 : 4,218.39 = 1,686.18 : x
  2. Step 2: Convert to fraction form
    2,811/4,218.39 = 1,686.18/x
  3. Step 3: Cross multiply
    2,811x = 4,218.39 × 1,686.18
  4. Step 4: Simplify right side
    2,811x = 7,112,964.85
  5. Step 5: Solve for x
    x = 7,112,964.85/2,811
  6. Step 6: Final answer
    x = 2,530.40

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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.