Home / 3,128.64-4,696.80-1,979.20

Finding the Fourth Proportional to 3,128.64, 4,696.80 and 1,979.20

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Solution

The fourth proportional to 3,128.64, 4,696.80 and 1,979.20 is: 2,971.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,128.64 : 4,696.80 = 1,979.20 : x
  2. Step 2: Convert to fraction form
    3,128.64/4,696.80 = 1,979.20/x
  3. Step 3: Cross multiply
    3,128.64x = 4,696.80 × 1,979.20
  4. Step 4: Simplify right side
    3,128.64x = 9,295,906.56
  5. Step 5: Solve for x
    x = 9,295,906.56/3,128.64
  6. Step 6: Final answer
    x = 2,971.23

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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.