Home / 1,212.59-1,819.20-390.98

Finding the Fourth Proportional to 1,212.59, 1,819.20 and 390.98

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Solution

The fourth proportional to 1,212.59, 1,819.20 and 390.98 is: 586.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.59 : 1,819.20 = 390.98 : x
  2. Step 2: Convert to fraction form
    1,212.59/1,819.20 = 390.98/x
  3. Step 3: Cross multiply
    1,212.59x = 1,819.20 × 390.98
  4. Step 4: Simplify right side
    1,212.59x = 711,270.82
  5. Step 5: Solve for x
    x = 711,270.82/1,212.59
  6. Step 6: Final answer
    x = 586.57

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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.