Home / 1,209.96-1,815.19-388.21

Finding the Fourth Proportional to 1,209.96, 1,815.19 and 388.21

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Solution

The fourth proportional to 1,209.96, 1,815.19 and 388.21 is: 582.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209.96 : 1,815.19 = 388.21 : x
  2. Step 2: Convert to fraction form
    1,209.96/1,815.19 = 388.21/x
  3. Step 3: Cross multiply
    1,209.96x = 1,815.19 × 388.21
  4. Step 4: Simplify right side
    1,209.96x = 704,674.91
  5. Step 5: Solve for x
    x = 704,674.91/1,209.96
  6. Step 6: Final answer
    x = 582.40

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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.