Home / 1,208.12-1,811.63-386.21

Finding the Fourth Proportional to 1,208.12, 1,811.63 and 386.21

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Solution

The fourth proportional to 1,208.12, 1,811.63 and 386.21 is: 579.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,208.12 : 1,811.63 = 386.21 : x
  2. Step 2: Convert to fraction form
    1,208.12/1,811.63 = 386.21/x
  3. Step 3: Cross multiply
    1,208.12x = 1,811.63 × 386.21
  4. Step 4: Simplify right side
    1,208.12x = 699,667.69
  5. Step 5: Solve for x
    x = 699,667.69/1,208.12
  6. Step 6: Final answer
    x = 579.14

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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.