Home / 1,211.10-1,816.65-723.90

Finding the Fourth Proportional to 1,211.10, 1,816.65 and 723.90

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Solution

The fourth proportional to 1,211.10, 1,816.65 and 723.90 is: 1,085.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.10 : 1,816.65 = 723.90 : x
  2. Step 2: Convert to fraction form
    1,211.10/1,816.65 = 723.90/x
  3. Step 3: Cross multiply
    1,211.10x = 1,816.65 × 723.90
  4. Step 4: Simplify right side
    1,211.10x = 1,315,072.94
  5. Step 5: Solve for x
    x = 1,315,072.94/1,211.10
  6. Step 6: Final answer
    x = 1,085.85

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Similar ratio
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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.