Home / 1,218.78-1,828.20-397.80

Finding the Fourth Proportional to 1,218.78, 1,828.20 and 397.80

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Solution

The fourth proportional to 1,218.78, 1,828.20 and 397.80 is: 596.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,218.78 : 1,828.20 = 397.80 : x
  2. Step 2: Convert to fraction form
    1,218.78/1,828.20 = 397.80/x
  3. Step 3: Cross multiply
    1,218.78x = 1,828.20 × 397.80
  4. Step 4: Simplify right side
    1,218.78x = 727,257.96
  5. Step 5: Solve for x
    x = 727,257.96/1,218.78
  6. Step 6: Final answer
    x = 596.71

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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.