Home / 1,280.24-1,920.78-458.75

Finding the Fourth Proportional to 1,280.24, 1,920.78 and 458.75

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Solution

The fourth proportional to 1,280.24, 1,920.78 and 458.75 is: 688.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.24 : 1,920.78 = 458.75 : x
  2. Step 2: Convert to fraction form
    1,280.24/1,920.78 = 458.75/x
  3. Step 3: Cross multiply
    1,280.24x = 1,920.78 × 458.75
  4. Step 4: Simplify right side
    1,280.24x = 881,148.22
  5. Step 5: Solve for x
    x = 881,148.22/1,280.24
  6. Step 6: Final answer
    x = 688.27

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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.