Home / 1,212.57-1,819.10-390.87

Finding the Fourth Proportional to 1,212.57, 1,819.10 and 390.87

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Solution

The fourth proportional to 1,212.57, 1,819.10 and 390.87 is: 586.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.57 : 1,819.10 = 390.87 : x
  2. Step 2: Convert to fraction form
    1,212.57/1,819.10 = 390.87/x
  3. Step 3: Cross multiply
    1,212.57x = 1,819.10 × 390.87
  4. Step 4: Simplify right side
    1,212.57x = 711,031.62
  5. Step 5: Solve for x
    x = 711,031.62/1,212.57
  6. Step 6: Final answer
    x = 586.38

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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.