Home / 1,209.35-1,813.68-387.20

Finding the Fourth Proportional to 1,209.35, 1,813.68 and 387.20

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Solution

The fourth proportional to 1,209.35, 1,813.68 and 387.20 is: 580.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209.35 : 1,813.68 = 387.20 : x
  2. Step 2: Convert to fraction form
    1,209.35/1,813.68 = 387.20/x
  3. Step 3: Cross multiply
    1,209.35x = 1,813.68 × 387.20
  4. Step 4: Simplify right side
    1,209.35x = 702,247.83
  5. Step 5: Solve for x
    x = 702,247.83/1,209.35
  6. Step 6: Final answer
    x = 580.68

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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.