Home / 1,287.18-1,788.63-1,273.80

Finding the Fourth Proportional to 1,287.18, 1,788.63 and 1,273.80

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Solution

The fourth proportional to 1,287.18, 1,788.63 and 1,273.80 is: 1,770.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.18 : 1,788.63 = 1,273.80 : x
  2. Step 2: Convert to fraction form
    1,287.18/1,788.63 = 1,273.80/x
  3. Step 3: Cross multiply
    1,287.18x = 1,788.63 × 1,273.80
  4. Step 4: Simplify right side
    1,287.18x = 2,278,356.89
  5. Step 5: Solve for x
    x = 2,278,356.89/1,287.18
  6. Step 6: Final answer
    x = 1,770.04

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.