Home / 1,211.34-1,816.89-389.64

Finding the Fourth Proportional to 1,211.34, 1,816.89 and 389.64

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Solution

The fourth proportional to 1,211.34, 1,816.89 and 389.64 is: 584.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.34 : 1,816.89 = 389.64 : x
  2. Step 2: Convert to fraction form
    1,211.34/1,816.89 = 389.64/x
  3. Step 3: Cross multiply
    1,211.34x = 1,816.89 × 389.64
  4. Step 4: Simplify right side
    1,211.34x = 707,933.02
  5. Step 5: Solve for x
    x = 707,933.02/1,211.34
  6. Step 6: Final answer
    x = 584.42

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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.