Home / 1,270.30-1,905.28-539.78

Finding the Fourth Proportional to 1,270.30, 1,905.28 and 539.78

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Solution

The fourth proportional to 1,270.30, 1,905.28 and 539.78 is: 809.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,270.30 : 1,905.28 = 539.78 : x
  2. Step 2: Convert to fraction form
    1,270.30/1,905.28 = 539.78/x
  3. Step 3: Cross multiply
    1,270.30x = 1,905.28 × 539.78
  4. Step 4: Simplify right side
    1,270.30x = 1,028,432.04
  5. Step 5: Solve for x
    x = 1,028,432.04/1,270.30
  6. Step 6: Final answer
    x = 809.60

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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.