Home / 1,211.18-1,816.72-431.15

Finding the Fourth Proportional to 1,211.18, 1,816.72 and 431.15

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Solution

The fourth proportional to 1,211.18, 1,816.72 and 431.15 is: 646.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.18 : 1,816.72 = 431.15 : x
  2. Step 2: Convert to fraction form
    1,211.18/1,816.72 = 431.15/x
  3. Step 3: Cross multiply
    1,211.18x = 1,816.72 × 431.15
  4. Step 4: Simplify right side
    1,211.18x = 783,278.83
  5. Step 5: Solve for x
    x = 783,278.83/1,211.18
  6. Step 6: Final answer
    x = 646.71

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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.