Home / 3,999.78-5,520-2,231.40

Finding the Fourth Proportional to 3,999.78, 5,520 and 2,231.40

Calculator

Solution

The fourth proportional to 3,999.78, 5,520 and 2,231.40 is: 3,079.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,999.78 : 5,520 = 2,231.40 : x
  2. Step 2: Convert to fraction form
    3,999.78/5,520 = 2,231.40/x
  3. Step 3: Cross multiply
    3,999.78x = 5,520 × 2,231.40
  4. Step 4: Simplify right side
    3,999.78x = 12,317,328
  5. Step 5: Solve for x
    x = 12,317,328/3,999.78
  6. Step 6: Final answer
    x = 3,079.50

Related Problems

Find fourth proportional to 1,999.89, 2,760 and 1,115.70
Half scale
Find fourth proportional to 7,999.56, 11,040 and 4,462.80
Double scale
Find fourth proportional to 4,000.78, 5,521.38 and 2,232.40
Similar ratio
Find fourth proportional to 5,999.67, 8,280 and 3,347.10
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.