Home / 1,211.10-1,815.30-517.65

Finding the Fourth Proportional to 1,211.10, 1,815.30 and 517.65

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Solution

The fourth proportional to 1,211.10, 1,815.30 and 517.65 is: 775.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.10 : 1,815.30 = 517.65 : x
  2. Step 2: Convert to fraction form
    1,211.10/1,815.30 = 517.65/x
  3. Step 3: Cross multiply
    1,211.10x = 1,815.30 × 517.65
  4. Step 4: Simplify right side
    1,211.10x = 939,690.05
  5. Step 5: Solve for x
    x = 939,690.05/1,211.10
  6. Step 6: Final answer
    x = 775.90

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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.