Home / 1,212.67-1,819.13-390.75

Finding the Fourth Proportional to 1,212.67, 1,819.13 and 390.75

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Solution

The fourth proportional to 1,212.67, 1,819.13 and 390.75 is: 586.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.67 : 1,819.13 = 390.75 : x
  2. Step 2: Convert to fraction form
    1,212.67/1,819.13 = 390.75/x
  3. Step 3: Cross multiply
    1,212.67x = 1,819.13 × 390.75
  4. Step 4: Simplify right side
    1,212.67x = 710,825.05
  5. Step 5: Solve for x
    x = 710,825.05/1,212.67
  6. Step 6: Final answer
    x = 586.17

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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.