Home / 1,209.72-1,815.24-479.81

Finding the Fourth Proportional to 1,209.72, 1,815.24 and 479.81

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Solution

The fourth proportional to 1,209.72, 1,815.24 and 479.81 is: 719.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209.72 : 1,815.24 = 479.81 : x
  2. Step 2: Convert to fraction form
    1,209.72/1,815.24 = 479.81/x
  3. Step 3: Cross multiply
    1,209.72x = 1,815.24 × 479.81
  4. Step 4: Simplify right side
    1,209.72x = 870,961.23
  5. Step 5: Solve for x
    x = 870,961.23/1,209.72
  6. Step 6: Final answer
    x = 719.97

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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.