Home / 1,280.19-1,920.45-458.55

Finding the Fourth Proportional to 1,280.19, 1,920.45 and 458.55

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Solution

The fourth proportional to 1,280.19, 1,920.45 and 458.55 is: 687.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.19 : 1,920.45 = 458.55 : x
  2. Step 2: Convert to fraction form
    1,280.19/1,920.45 = 458.55/x
  3. Step 3: Cross multiply
    1,280.19x = 1,920.45 × 458.55
  4. Step 4: Simplify right side
    1,280.19x = 880,622.35
  5. Step 5: Solve for x
    x = 880,622.35/1,280.19
  6. Step 6: Final answer
    x = 687.88

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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.