Home / 1,211.30-1,815.70-479.87

Finding the Fourth Proportional to 1,211.30, 1,815.70 and 479.87

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Solution

The fourth proportional to 1,211.30, 1,815.70 and 479.87 is: 719.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.30 : 1,815.70 = 479.87 : x
  2. Step 2: Convert to fraction form
    1,211.30/1,815.70 = 479.87/x
  3. Step 3: Cross multiply
    1,211.30x = 1,815.70 × 479.87
  4. Step 4: Simplify right side
    1,211.30x = 871,299.96
  5. Step 5: Solve for x
    x = 871,299.96/1,211.30
  6. Step 6: Final answer
    x = 719.31

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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.