Home / 1,211.31-1,816.36-389.30

Finding the Fourth Proportional to 1,211.31, 1,816.36 and 389.30

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Solution

The fourth proportional to 1,211.31, 1,816.36 and 389.30 is: 583.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.31 : 1,816.36 = 389.30 : x
  2. Step 2: Convert to fraction form
    1,211.31/1,816.36 = 389.30/x
  3. Step 3: Cross multiply
    1,211.31x = 1,816.36 × 389.30
  4. Step 4: Simplify right side
    1,211.31x = 707,098.89
  5. Step 5: Solve for x
    x = 707,098.89/1,211.31
  6. Step 6: Final answer
    x = 583.75

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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.