Home / 1,212.77-1,819.31-390.84

Finding the Fourth Proportional to 1,212.77, 1,819.31 and 390.84

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Solution

The fourth proportional to 1,212.77, 1,819.31 and 390.84 is: 586.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.77 : 1,819.31 = 390.84 : x
  2. Step 2: Convert to fraction form
    1,212.77/1,819.31 = 390.84/x
  3. Step 3: Cross multiply
    1,212.77x = 1,819.31 × 390.84
  4. Step 4: Simplify right side
    1,212.77x = 711,057.17
  5. Step 5: Solve for x
    x = 711,057.17/1,212.77
  6. Step 6: Final answer
    x = 586.31

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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.