Home / 1,289.88-1,934.70-519.80

Finding the Fourth Proportional to 1,289.88, 1,934.70 and 519.80

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Solution

The fourth proportional to 1,289.88, 1,934.70 and 519.80 is: 779.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.88 : 1,934.70 = 519.80 : x
  2. Step 2: Convert to fraction form
    1,289.88/1,934.70 = 519.80/x
  3. Step 3: Cross multiply
    1,289.88x = 1,934.70 × 519.80
  4. Step 4: Simplify right side
    1,289.88x = 1,005,657.06
  5. Step 5: Solve for x
    x = 1,005,657.06/1,289.88
  6. Step 6: Final answer
    x = 779.65

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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.