Home / 1,212.34-1,818.55-390.62

Finding the Fourth Proportional to 1,212.34, 1,818.55 and 390.62

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Solution

The fourth proportional to 1,212.34, 1,818.55 and 390.62 is: 585.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.34 : 1,818.55 = 390.62 : x
  2. Step 2: Convert to fraction form
    1,212.34/1,818.55 = 390.62/x
  3. Step 3: Cross multiply
    1,212.34x = 1,818.55 × 390.62
  4. Step 4: Simplify right side
    1,212.34x = 710,367.04
  5. Step 5: Solve for x
    x = 710,367.04/1,212.34
  6. Step 6: Final answer
    x = 585.95

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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.