Home / 1,979.21-2,963.14-1,328.78

Finding the Fourth Proportional to 1,979.21, 2,963.14 and 1,328.78

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Solution

The fourth proportional to 1,979.21, 2,963.14 and 1,328.78 is: 1,989.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,979.21 : 2,963.14 = 1,328.78 : x
  2. Step 2: Convert to fraction form
    1,979.21/2,963.14 = 1,328.78/x
  3. Step 3: Cross multiply
    1,979.21x = 2,963.14 × 1,328.78
  4. Step 4: Simplify right side
    1,979.21x = 3,937,361.17
  5. Step 5: Solve for x
    x = 3,937,361.17/1,979.21
  6. Step 6: Final answer
    x = 1,989.36

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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.