Home / 1,428.21-2,142.45-388.22

Finding the Fourth Proportional to 1,428.21, 2,142.45 and 388.22

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Solution

The fourth proportional to 1,428.21, 2,142.45 and 388.22 is: 582.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,428.21 : 2,142.45 = 388.22 : x
  2. Step 2: Convert to fraction form
    1,428.21/2,142.45 = 388.22/x
  3. Step 3: Cross multiply
    1,428.21x = 2,142.45 × 388.22
  4. Step 4: Simplify right side
    1,428.21x = 831,741.94
  5. Step 5: Solve for x
    x = 831,741.94/1,428.21
  6. Step 6: Final answer
    x = 582.37

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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.