Home / 1,280.05-1,920.30-458.80

Finding the Fourth Proportional to 1,280.05, 1,920.30 and 458.80

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Solution

The fourth proportional to 1,280.05, 1,920.30 and 458.80 is: 688.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.05 : 1,920.30 = 458.80 : x
  2. Step 2: Convert to fraction form
    1,280.05/1,920.30 = 458.80/x
  3. Step 3: Cross multiply
    1,280.05x = 1,920.30 × 458.80
  4. Step 4: Simplify right side
    1,280.05x = 881,033.64
  5. Step 5: Solve for x
    x = 881,033.64/1,280.05
  6. Step 6: Final answer
    x = 688.28

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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.