Home / 270.16-405.20-77.78

Finding the Fourth Proportional to 270.16, 405.20 and 77.78

Calculator

Solution

The fourth proportional to 270.16, 405.20 and 77.78 is: 116.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    270.16 : 405.20 = 77.78 : x
  2. Step 2: Convert to fraction form
    270.16/405.20 = 77.78/x
  3. Step 3: Cross multiply
    270.16x = 405.20 × 77.78
  4. Step 4: Simplify right side
    270.16x = 31,517.66
  5. Step 5: Solve for x
    x = 31,517.66/270.16
  6. Step 6: Final answer
    x = 116.66

Related Problems

Find fourth proportional to 135.08, 202.60 and 38.89
Half scale
Find fourth proportional to 540.32, 810.41 and 155.57
Double scale
Find fourth proportional to 271.16, 406.70 and 78.78
Similar ratio
Find fourth proportional to 405.24, 607.80 and 116.67
1.5x scale

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.