Home / 1,211.70-1,816.47-480.78

Finding the Fourth Proportional to 1,211.70, 1,816.47 and 480.78

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Solution

The fourth proportional to 1,211.70, 1,816.47 and 480.78 is: 720.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.70 : 1,816.47 = 480.78 : x
  2. Step 2: Convert to fraction form
    1,211.70/1,816.47 = 480.78/x
  3. Step 3: Cross multiply
    1,211.70x = 1,816.47 × 480.78
  4. Step 4: Simplify right side
    1,211.70x = 873,322.45
  5. Step 5: Solve for x
    x = 873,322.45/1,211.70
  6. Step 6: Final answer
    x = 720.74

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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.