Home / 1,428.90-2,141.89-811.30

Finding the Fourth Proportional to 1,428.90, 2,141.89 and 811.30

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Solution

The fourth proportional to 1,428.90, 2,141.89 and 811.30 is: 1,216.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,428.90 : 2,141.89 = 811.30 : x
  2. Step 2: Convert to fraction form
    1,428.90/2,141.89 = 811.30/x
  3. Step 3: Cross multiply
    1,428.90x = 2,141.89 × 811.30
  4. Step 4: Simplify right side
    1,428.90x = 1,737,715.36
  5. Step 5: Solve for x
    x = 1,737,715.36/1,428.90
  6. Step 6: Final answer
    x = 1,216.12

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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.