Home / 1,639.20-2,458.80-485.04

Finding the Fourth Proportional to 1,639.20, 2,458.80 and 485.04

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Solution

The fourth proportional to 1,639.20, 2,458.80 and 485.04 is: 727.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,639.20 : 2,458.80 = 485.04 : x
  2. Step 2: Convert to fraction form
    1,639.20/2,458.80 = 485.04/x
  3. Step 3: Cross multiply
    1,639.20x = 2,458.80 × 485.04
  4. Step 4: Simplify right side
    1,639.20x = 1,192,616.35
  5. Step 5: Solve for x
    x = 1,192,616.35/1,639.20
  6. Step 6: Final answer
    x = 727.56

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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.