Home / 1,280.13-1,920.60-664.29

Finding the Fourth Proportional to 1,280.13, 1,920.60 and 664.29

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Solution

The fourth proportional to 1,280.13, 1,920.60 and 664.29 is: 996.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.13 : 1,920.60 = 664.29 : x
  2. Step 2: Convert to fraction form
    1,280.13/1,920.60 = 664.29/x
  3. Step 3: Cross multiply
    1,280.13x = 1,920.60 × 664.29
  4. Step 4: Simplify right side
    1,280.13x = 1,275,835.37
  5. Step 5: Solve for x
    x = 1,275,835.37/1,280.13
  6. Step 6: Final answer
    x = 996.65

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1.5x scale

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.