Home / 1,285.52-1,912.90-1,281.20

Finding the Fourth Proportional to 1,285.52, 1,912.90 and 1,281.20

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Solution

The fourth proportional to 1,285.52, 1,912.90 and 1,281.20 is: 1,906.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.52 : 1,912.90 = 1,281.20 : x
  2. Step 2: Convert to fraction form
    1,285.52/1,912.90 = 1,281.20/x
  3. Step 3: Cross multiply
    1,285.52x = 1,912.90 × 1,281.20
  4. Step 4: Simplify right side
    1,285.52x = 2,450,807.48
  5. Step 5: Solve for x
    x = 2,450,807.48/1,285.52
  6. Step 6: Final answer
    x = 1,906.47

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.