Home / 1,979.28-2,969.52-680.76

Finding the Fourth Proportional to 1,979.28, 2,969.52 and 680.76

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Solution

The fourth proportional to 1,979.28, 2,969.52 and 680.76 is: 1,021.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,979.28 : 2,969.52 = 680.76 : x
  2. Step 2: Convert to fraction form
    1,979.28/2,969.52 = 680.76/x
  3. Step 3: Cross multiply
    1,979.28x = 2,969.52 × 680.76
  4. Step 4: Simplify right side
    1,979.28x = 2,021,530.44
  5. Step 5: Solve for x
    x = 2,021,530.44/1,979.28
  6. Step 6: Final answer
    x = 1,021.35

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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.