Home / 813.20-1,220.20-380.28

Finding the Fourth Proportional to 813.20, 1,220.20 and 380.28

Calculator

Solution

The fourth proportional to 813.20, 1,220.20 and 380.28 is: 570.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.20 : 1,220.20 = 380.28 : x
  2. Step 2: Convert to fraction form
    813.20/1,220.20 = 380.28/x
  3. Step 3: Cross multiply
    813.20x = 1,220.20 × 380.28
  4. Step 4: Simplify right side
    813.20x = 464,017.66
  5. Step 5: Solve for x
    x = 464,017.66/813.20
  6. Step 6: Final answer
    x = 570.61

Related Problems

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.