Home / 1,428.28-2,142.56-388.29

Finding the Fourth Proportional to 1,428.28, 2,142.56 and 388.29

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Solution

The fourth proportional to 1,428.28, 2,142.56 and 388.29 is: 582.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,428.28 : 2,142.56 = 388.29 : x
  2. Step 2: Convert to fraction form
    1,428.28/2,142.56 = 388.29/x
  3. Step 3: Cross multiply
    1,428.28x = 2,142.56 × 388.29
  4. Step 4: Simplify right side
    1,428.28x = 831,934.62
  5. Step 5: Solve for x
    x = 831,934.62/1,428.28
  6. Step 6: Final answer
    x = 582.47

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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.