Home / 1,285.88-1,928.70-515.80

Finding the Fourth Proportional to 1,285.88, 1,928.70 and 515.80

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Solution

The fourth proportional to 1,285.88, 1,928.70 and 515.80 is: 773.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.88 : 1,928.70 = 515.80 : x
  2. Step 2: Convert to fraction form
    1,285.88/1,928.70 = 515.80/x
  3. Step 3: Cross multiply
    1,285.88x = 1,928.70 × 515.80
  4. Step 4: Simplify right side
    1,285.88x = 994,823.46
  5. Step 5: Solve for x
    x = 994,823.46/1,285.88
  6. Step 6: Final answer
    x = 773.65

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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.