Home / 1,211.10-1,815.93-389.40

Finding the Fourth Proportional to 1,211.10, 1,815.93 and 389.40

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Solution

The fourth proportional to 1,211.10, 1,815.93 and 389.40 is: 583.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.10 : 1,815.93 = 389.40 : x
  2. Step 2: Convert to fraction form
    1,211.10/1,815.93 = 389.40/x
  3. Step 3: Cross multiply
    1,211.10x = 1,815.93 × 389.40
  4. Step 4: Simplify right side
    1,211.10x = 707,123.14
  5. Step 5: Solve for x
    x = 707,123.14/1,211.10
  6. Step 6: Final answer
    x = 583.87

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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.