Home / 1,280.32-1,920.40-458.60

Finding the Fourth Proportional to 1,280.32, 1,920.40 and 458.60

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Solution

The fourth proportional to 1,280.32, 1,920.40 and 458.60 is: 687.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.32 : 1,920.40 = 458.60 : x
  2. Step 2: Convert to fraction form
    1,280.32/1,920.40 = 458.60/x
  3. Step 3: Cross multiply
    1,280.32x = 1,920.40 × 458.60
  4. Step 4: Simplify right side
    1,280.32x = 880,684.69
  5. Step 5: Solve for x
    x = 880,684.69/1,280.32
  6. Step 6: Final answer
    x = 687.86

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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.